diff --git a/pystac/extensions/virtual_assets.py b/pystac/extensions/virtual_assets.py
new file mode 100644
index 000000000..8d3f729c1
--- /dev/null
+++ b/pystac/extensions/virtual_assets.py
@@ -0,0 +1,98 @@
+from __future__ import annotations
+
+from typing import (
+    Any,
+    Dict,
+    Iterable,
+    List,
+    Optional,
+    TypeVar,
+    Union,
+)
+from pystac.extensions.base import (
+    ExtensionManagementMixin,
+    PropertiesExtension
+)
+import pystac
+S = TypeVar("S", bound=pystac.STACObject)
+
+PREFIX = "virtual:"
+HREFS_PROP = PREFIX + "hrefs"
+SCHEMA_URI = "https://github.com/stac-extensions/virtual-assets/blob/main/json-schema/schema.json"
+
+class VirtualAssetsExtension(
+    PropertiesExtension, ExtensionManagementMixin[Union[pystac.Item, pystac.Collection]]
+):
+    """A class that can be used to extend the properties of a :class:`~pystac.Asset`
+    with properties from the :stac-ext:`Virtual Assets Extension <virtual-assets>`.
+
+    To create an instance of :class:`VirtualAssetsExtension`, use the
+    :meth:`VirtualAssetsExtension.ext` method. For example:
+
+    .. code-block:: python
+
+       >>> asset: pystac.Asset = ...
+       >>> virtual_assets_ext = VirtualAssetsExtension.ext(asset)
+    """
+    asset_href: str
+    """The ``href`` value of the :class:`~pystac.Asset` being extended."""
+
+    properties: Dict[str, Any]
+    """The :class:`~pystac.Asset` fields, including extension properties."""
+
+    additional_read_properties: Optional[Iterable[Dict[str, Any]]] = None
+    """If present, this will be a list containing 1 dictionary representing the
+    properties of the owning :class:`~pystac.Item`."""
+
+    def __init__(self, asset: pystac.Asset):
+        self.asset_href = asset.href
+        self.properties = asset.extra_fields
+        if asset.owner and isinstance(asset.owner, pystac.Item):
+            self.additional_read_properties = [asset.owner.properties]
+
+    def __repr__(self) -> str:
+        return "<AssetVirtualAssetsExtension Asset href={}>".format(self.asset_href)
+    
+    def apply(
+        self,
+        hrefs: List[str]
+    ) -> None:
+        """Applies virtual assets extension properties to the extended Item.
+
+        Args:
+            hrefs : List of hrefs to virtual assets.
+        """
+        self.hrefs = hrefs
+
+    @property
+    def hrefs(self) -> List[str]:
+        """Get or sets the hrefs of the virtual asset."""
+        return self._get_property(HREFS_PROP, int)
+
+    @classmethod
+    def get_schema_uri(cls) -> str:
+        return SCHEMA_URI
+
+    @classmethod
+    # TODO: remove this once extension is released.
+    def has_extension(cls, obj: S) -> bool:
+        """Check if the given object implements this extension by checking
+        :attr:`pystac.STACObject.stac_extensions` for this extension's schema URI."""
+        schema_uri = cls.get_schema_uri()
+
+        return obj.stac_extensions is not None and any(
+            uri == schema_uri for uri in obj.stac_extensions
+        )    
+
+    @classmethod
+    def ext(cls, obj: pystac.Asset, add_if_missing: bool = False) -> VirtualAssetsExtension:
+        """Extends the given STAC Object with properties from the :stac-ext:`Virtual Asset
+        Extension <virtual-assets>`.
+
+        This extension can be applied to instances of :class:`~pystac.Asset`.
+        """
+        if isinstance(obj, pystac.Asset):
+            cls.validate_owner_has_extension(obj, add_if_missing)
+            return cls(obj)
+        else:
+            raise pystac.ExtensionTypeError(cls._ext_error_message(obj))    
\ No newline at end of file
diff --git a/tests/data-files/virtual-assets/sentinel-item.json b/tests/data-files/virtual-assets/sentinel-item.json
new file mode 100644
index 000000000..6d6ee9c3a
--- /dev/null
+++ b/tests/data-files/virtual-assets/sentinel-item.json
@@ -0,0 +1,752 @@
+{
+    "type": "Feature",
+    "stac_version": "1.0.0-rc.4",
+    "stac_extensions": [
+      "https://stac-extensions.github.io/eo/v1.0.0/schema.json",
+      "https://stac-extensions.github.io/view/v1.0.0/schema.json",
+      "https://stac-extensions.github.io/projection/v1.0.0/schema.json",
+      "https://stac-extensions.github.io/raster/v1.0.0/schema.json",
+      "https://github.com/stac-extensions/virtual-assets/blob/main/json-schema/schema.json"
+    ],
+    "id": "S2B_33SVB_20210221_0_L2A",
+    "bbox": [
+      13.86148243891681,
+      36.95257399124932,
+      15.111074610520053,
+      37.94752813015372
+    ],
+    "geometry": {
+      "type": "Polygon",
+      "coordinates": [
+        [
+          [
+            13.876381589019879,
+            36.95257399124932
+          ],
+          [
+            13.86148243891681,
+            37.942072015005024
+          ],
+          [
+            15.111074610520053,
+            37.94752813015372
+          ],
+          [
+            15.109620666835209,
+            36.95783951241028
+          ],
+          [
+            13.876381589019879,
+            36.95257399124932
+          ]
+        ]
+      ]
+    },
+    "properties": {
+      "datetime": "2021-02-21T10:00:17Z",
+      "platform": "sentinel-2b",
+      "constellation": "sentinel-2",
+      "instruments": [
+        "msi"
+      ],
+      "gsd": 10,
+      "view:off_nadir": 0,
+      "proj:epsg": 32633,
+      "sentinel:utm_zone": 33,
+      "sentinel:latitude_band": "S",
+      "sentinel:grid_square": "VB",
+      "sentinel:sequence": "0",
+      "sentinel:product_id": "S2B_MSIL2A_20210221T095029_N0214_R079_T33SVB_20210221T115149",
+      "sentinel:data_coverage": 100,
+      "eo:cloud_cover": 21.22,
+      "sentinel:valid_cloud_cover": true
+    },
+    "collection": "sentinel-s2-l2a-cogs",
+    "assets": {
+      "thumbnail": {
+        "title": "Thumbnail",
+        "type": "image/png",
+        "roles": [
+          "thumbnail"
+        ],
+        "href": "https://roda.sentinel-hub.com/sentinel-s2-l1c/tiles/33/S/VB/2021/2/21/0/preview.jpg"
+      },
+      "overview": {
+        "title": "True color image",
+        "type": "image/tiff; application=geotiff; profile=cloud-optimized",
+        "roles": [
+          "overview"
+        ],
+        "gsd": 10,
+        "eo:bands": [
+          {
+            "name": "B04",
+            "common_name": "red",
+            "center_wavelength": 0.6645,
+            "full_width_half_max": 0.038
+          },
+          {
+            "name": "B03",
+            "common_name": "green",
+            "center_wavelength": 0.56,
+            "full_width_half_max": 0.045
+          },
+          {
+            "name": "B02",
+            "common_name": "blue",
+            "center_wavelength": 0.4966,
+            "full_width_half_max": 0.098
+          }
+        ],
+        "href": "https://sentinel-cogs.s3.us-west-2.amazonaws.com/sentinel-s2-l2a-cogs/33/S/VB/2021/2/S2B_33SVB_20210221_0_L2A/L2A_PVI.tif",
+        "proj:shape": [
+          343,
+          343
+        ],
+        "proj:transform": [
+          320,
+          0,
+          399960,
+          0,
+          -320,
+          4200000,
+          0,
+          0,
+          1
+        ]
+      },
+      "info": {
+        "title": "Original JSON metadata",
+        "type": "application/json",
+        "roles": [
+          "metadata"
+        ],
+        "href": "https://roda.sentinel-hub.com/sentinel-s2-l2a/tiles/33/S/VB/2021/2/21/0/tileInfo.json"
+      },
+      "metadata": {
+        "title": "Original XML metadata",
+        "type": "application/xml",
+        "roles": [
+          "metadata"
+        ],
+        "href": "https://roda.sentinel-hub.com/sentinel-s2-l2a/tiles/33/S/VB/2021/2/21/0/metadata.xml"
+      },
+      "visual": {
+        "title": "True color image",
+        "type": "image/tiff; application=geotiff; profile=cloud-optimized",
+        "roles": [
+          "overview"
+        ],
+        "gsd": 10,
+        "eo:bands": [
+          {
+            "name": "B04",
+            "common_name": "red",
+            "center_wavelength": 0.6645,
+            "full_width_half_max": 0.038
+          },
+          {
+            "name": "B03",
+            "common_name": "green",
+            "center_wavelength": 0.56,
+            "full_width_half_max": 0.045
+          },
+          {
+            "name": "B02",
+            "common_name": "blue",
+            "center_wavelength": 0.4966,
+            "full_width_half_max": 0.098
+          }
+        ],
+        "href": "https://sentinel-cogs.s3.us-west-2.amazonaws.com/sentinel-s2-l2a-cogs/33/S/VB/2021/2/S2B_33SVB_20210221_0_L2A/TCI.tif",
+        "proj:shape": [
+          10980,
+          10980
+        ],
+        "proj:transform": [
+          10,
+          0,
+          399960,
+          0,
+          -10,
+          4200000,
+          0,
+          0,
+          1
+        ]
+      },
+      "B01": {
+        "title": "Band 1 (coastal)",
+        "type": "image/tiff; application=geotiff; profile=cloud-optimized",
+        "roles": [
+          "data"
+        ],
+        "gsd": 60,
+        "eo:bands": [
+          {
+            "name": "B01",
+            "common_name": "coastal",
+            "center_wavelength": 0.4439,
+            "full_width_half_max": 0.027
+          }
+        ],
+        "href": "https://sentinel-cogs.s3.us-west-2.amazonaws.com/sentinel-s2-l2a-cogs/33/S/VB/2021/2/S2B_33SVB_20210221_0_L2A/B01.tif",
+        "proj:shape": [
+          1830,
+          1830
+        ],
+        "proj:transform": [
+          60,
+          0,
+          399960,
+          0,
+          -60,
+          4200000,
+          0,
+          0,
+          1
+        ],
+        "raster:bands": [
+          {
+            "data_type": "uint16",
+            "nodata": 0,
+            "stats_min": 1,
+            "stats_max": 20567,
+            "stats_mean": 2339.4759595597,
+            "stats_stddev": 3026.6973619954,
+            "stats_valid_percent": 99.83,
+            "values": [
+              {
+                "name": "BOA reflectance",
+                "unit": "W/m²/sr/μm"
+              }
+            ]
+          }
+        ]
+      },
+      "B02": {
+        "title": "Band 2 (blue)",
+        "type": "image/tiff; application=geotiff; profile=cloud-optimized",
+        "roles": [
+          "data"
+        ],
+        "gsd": 10,
+        "eo:bands": [
+          {
+            "name": "B02",
+            "common_name": "blue",
+            "center_wavelength": 0.4966,
+            "full_width_half_max": 0.098
+          }
+        ],
+        "href": "https://sentinel-cogs.s3.us-west-2.amazonaws.com/sentinel-s2-l2a-cogs/33/S/VB/2021/2/S2B_33SVB_20210221_0_L2A/B02.tif",
+        "proj:shape": [
+          10980,
+          10980
+        ],
+        "proj:transform": [
+          10,
+          0,
+          399960,
+          0,
+          -10,
+          4200000,
+          0,
+          0,
+          1
+        ],
+        "raster:bands": [
+          {
+            "data_type": "uint16",
+            "nodata": 0,
+            "stats_min": 1,
+            "stats_max": 19264,
+            "stats_mean": 2348.069117847,
+            "stats_stddev": 2916.5446249911,
+            "stats_valid_percent": 99.99,
+            "values": [
+              {
+                "name": "BOA reflectance",
+                "unit": "W/m²/sr/μm"
+              }
+            ]
+          }
+        ]
+      },
+      "B03": {
+        "title": "Band 3 (green)",
+        "type": "image/tiff; application=geotiff; profile=cloud-optimized",
+        "roles": [
+          "data"
+        ],
+        "gsd": 10,
+        "eo:bands": [
+          {
+            "name": "B03",
+            "common_name": "green",
+            "center_wavelength": 0.56,
+            "full_width_half_max": 0.045
+          }
+        ],
+        "href": "https://sentinel-cogs.s3.us-west-2.amazonaws.com/sentinel-s2-l2a-cogs/33/S/VB/2021/2/S2B_33SVB_20210221_0_L2A/B03.tif",
+        "proj:shape": [
+          10980,
+          10980
+        ],
+        "proj:transform": [
+          10,
+          0,
+          399960,
+          0,
+          -10,
+          4200000,
+          0,
+          0,
+          1
+        ],
+        "raster:bands": [
+          {
+            "data_type": "uint16",
+            "nodata": 0,
+            "stats_min": 1,
+            "stats_max": 18064,
+            "stats_mean": 2384.4680007438,
+            "stats_stddev": 2675.410513295,
+            "stats_valid_percent": 99.999,
+            "values": [
+              {
+                "name": "BOA reflectance",
+                "unit": "W/m²/sr/μm"
+              }
+            ]
+          }
+        ]
+      },
+      "B04": {
+        "title": "Band 4 (red)",
+        "type": "image/tiff; application=geotiff; profile=cloud-optimized",
+        "roles": [
+          "data"
+        ],
+        "gsd": 10,
+        "eo:bands": [
+          {
+            "name": "B04",
+            "common_name": "red",
+            "center_wavelength": 0.6645,
+            "full_width_half_max": 0.038
+          }
+        ],
+        "href": "https://sentinel-cogs.s3.us-west-2.amazonaws.com/sentinel-s2-l2a-cogs/33/S/VB/2021/2/S2B_33SVB_20210221_0_L2A/B04.tif",
+        "proj:shape": [
+          10980,
+          10980
+        ],
+        "proj:transform": [
+          10,
+          0,
+          399960,
+          0,
+          -10,
+          4200000,
+          0,
+          0,
+          1
+        ],
+        "raster:bands": [
+          {
+            "data_type": "uint16",
+            "nodata": 0,
+            "stats_min": 1,
+            "stats_max": 17200,
+            "stats_mean": 2273.9667970732,
+            "stats_stddev": 2618.272802792,
+            "stats_valid_percent": 99.999,
+            "values": [
+              {
+                "name": "BOA reflectance",
+                "unit": "W/m²/sr/μm"
+              }
+            ]
+          }
+        ]
+      },
+      "B05": {
+        "title": "Band 5",
+        "type": "image/tiff; application=geotiff; profile=cloud-optimized",
+        "roles": [
+          "data"
+        ],
+        "gsd": 20,
+        "eo:bands": [
+          {
+            "name": "B05",
+            "center_wavelength": 0.7039,
+            "full_width_half_max": 0.019
+          }
+        ],
+        "href": "https://sentinel-cogs.s3.us-west-2.amazonaws.com/sentinel-s2-l2a-cogs/33/S/VB/2021/2/S2B_33SVB_20210221_0_L2A/B05.tif",
+        "proj:shape": [
+          5490,
+          5490
+        ],
+        "proj:transform": [
+          20,
+          0,
+          399960,
+          0,
+          -20,
+          4200000,
+          0,
+          0,
+          1
+        ],
+        "raster:bands": [
+          {
+            "data_type": "uint16",
+            "nodata": 0,
+            "stats_min": 1,
+            "stats_max": 16842,
+            "stats_mean": 2634.1490243416,
+            "stats_stddev": 2634.1490243416,
+            "stats_valid_percent": 99.999,
+            "values": [
+              {
+                "name": "BOA reflectance",
+                "unit": "W/m²/sr/μm"
+              }
+            ]
+          }
+        ]
+      },
+      "B06": {
+        "title": "Band 6",
+        "type": "image/tiff; application=geotiff; profile=cloud-optimized",
+        "roles": [
+          "data"
+        ],
+        "gsd": 20,
+        "eo:bands": [
+          {
+            "name": "B06",
+            "center_wavelength": 0.7402,
+            "full_width_half_max": 0.018
+          }
+        ],
+        "href": "https://sentinel-cogs.s3.us-west-2.amazonaws.com/sentinel-s2-l2a-cogs/33/S/VB/2021/2/S2B_33SVB_20210221_0_L2A/B06.tif",
+        "proj:shape": [
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+          5490
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+          20,
+          0,
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+          1
+        ],
+        "raster:bands": [
+          {
+            "data_type": "uint16",
+            "nodata": 0,
+            "stats_min": 1,
+            "stats_max": 16502,
+            "stats_mean": 3329.8844628619,
+            "stats_stddev": 2303.0096294469,
+            "stats_valid_percent": 99.999,
+            "values": [
+              {
+                "name": "BOA reflectance",
+                "unit": "W/m²/sr/μm"
+              }
+            ]
+          }
+        ]
+      },
+      "B07": {
+        "title": "Band 7",
+        "type": "image/tiff; application=geotiff; profile=cloud-optimized",
+        "roles": [
+          "data"
+        ],
+        "gsd": 20,
+        "eo:bands": [
+          {
+            "name": "B07",
+            "center_wavelength": 0.7825,
+            "full_width_half_max": 0.028
+          }
+        ],
+        "href": "https://sentinel-cogs.s3.us-west-2.amazonaws.com/sentinel-s2-l2a-cogs/33/S/VB/2021/2/S2B_33SVB_20210221_0_L2A/B07.tif",
+        "proj:shape": [
+          5490,
+          5490
+        ],
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+          20,
+          0,
+          399960,
+          0,
+          -20,
+          4200000,
+          0,
+          0,
+          1
+        ]
+      },
+      "B08": {
+        "title": "Band 8 (nir)",
+        "type": "image/tiff; application=geotiff; profile=cloud-optimized",
+        "roles": [
+          "data"
+        ],
+        "gsd": 10,
+        "eo:bands": [
+          {
+            "name": "B08",
+            "common_name": "nir",
+            "center_wavelength": 0.8351,
+            "full_width_half_max": 0.145
+          }
+        ],
+        "href": "https://sentinel-cogs.s3.us-west-2.amazonaws.com/sentinel-s2-l2a-cogs/33/S/VB/2021/2/S2B_33SVB_20210221_0_L2A/B08.tif",
+        "proj:shape": [
+          10980,
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+        ],
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+          0,
+          -10,
+          4200000,
+          0,
+          0,
+          1
+        ]
+      },
+      "B8A": {
+        "title": "Band 8A",
+        "type": "image/tiff; application=geotiff; profile=cloud-optimized",
+        "roles": [
+          "data"
+        ],
+        "gsd": 20,
+        "eo:bands": [
+          {
+            "name": "B8A",
+            "center_wavelength": 0.8648,
+            "full_width_half_max": 0.033
+          }
+        ],
+        "href": "https://sentinel-cogs.s3.us-west-2.amazonaws.com/sentinel-s2-l2a-cogs/33/S/VB/2021/2/S2B_33SVB_20210221_0_L2A/B8A.tif",
+        "proj:shape": [
+          5490,
+          5490
+        ],
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+          0,
+          399960,
+          0,
+          -20,
+          4200000,
+          0,
+          0,
+          1
+        ]
+      },
+      "B09": {
+        "title": "Band 9",
+        "type": "image/tiff; application=geotiff; profile=cloud-optimized",
+        "roles": [
+          "data"
+        ],
+        "gsd": 60,
+        "eo:bands": [
+          {
+            "name": "B09",
+            "center_wavelength": 0.945,
+            "full_width_half_max": 0.026
+          }
+        ],
+        "href": "https://sentinel-cogs.s3.us-west-2.amazonaws.com/sentinel-s2-l2a-cogs/33/S/VB/2021/2/S2B_33SVB_20210221_0_L2A/B09.tif",
+        "proj:shape": [
+          1830,
+          1830
+        ],
+        "proj:transform": [
+          60,
+          0,
+          399960,
+          0,
+          -60,
+          4200000,
+          0,
+          0,
+          1
+        ]
+      },
+      "B11": {
+        "title": "Band 11 (swir16)",
+        "type": "image/tiff; application=geotiff; profile=cloud-optimized",
+        "roles": [
+          "data"
+        ],
+        "gsd": 20,
+        "eo:bands": [
+          {
+            "name": "B11",
+            "common_name": "swir16",
+            "center_wavelength": 1.6137,
+            "full_width_half_max": 0.143
+          }
+        ],
+        "href": "https://sentinel-cogs.s3.us-west-2.amazonaws.com/sentinel-s2-l2a-cogs/33/S/VB/2021/2/S2B_33SVB_20210221_0_L2A/B11.tif",
+        "proj:shape": [
+          5490,
+          5490
+        ],
+        "proj:transform": [
+          20,
+          0,
+          399960,
+          0,
+          -20,
+          4200000,
+          0,
+          0,
+          1
+        ]
+      },
+      "B12": {
+        "title": "Band 12 (swir22)",
+        "type": "image/tiff; application=geotiff; profile=cloud-optimized",
+        "roles": [
+          "data"
+        ],
+        "gsd": 20,
+        "eo:bands": [
+          {
+            "name": "B12",
+            "common_name": "swir22",
+            "center_wavelength": 2.22024,
+            "full_width_half_max": 0.242
+          }
+        ],
+        "href": "https://sentinel-cogs.s3.us-west-2.amazonaws.com/sentinel-s2-l2a-cogs/33/S/VB/2021/2/S2B_33SVB_20210221_0_L2A/B12.tif",
+        "proj:shape": [
+          5490,
+          5490
+        ],
+        "proj:transform": [
+          20,
+          0,
+          399960,
+          0,
+          -20,
+          4200000,
+          0,
+          0,
+          1
+        ]
+      },
+      "AOT": {
+        "title": "Aerosol Optical Thickness (AOT)",
+        "type": "image/tiff; application=geotiff; profile=cloud-optimized",
+        "roles": [
+          "data"
+        ],
+        "href": "https://sentinel-cogs.s3.us-west-2.amazonaws.com/sentinel-s2-l2a-cogs/33/S/VB/2021/2/S2B_33SVB_20210221_0_L2A/AOT.tif",
+        "proj:shape": [
+          1830,
+          1830
+        ],
+        "proj:transform": [
+          60,
+          0,
+          399960,
+          0,
+          -60,
+          4200000,
+          0,
+          0,
+          1
+        ]
+      },
+      "WVP": {
+        "title": "Water Vapour (WVP)",
+        "type": "image/tiff; application=geotiff; profile=cloud-optimized",
+        "roles": [
+          "data"
+        ],
+        "href": "https://sentinel-cogs.s3.us-west-2.amazonaws.com/sentinel-s2-l2a-cogs/33/S/VB/2021/2/S2B_33SVB_20210221_0_L2A/WVP.tif",
+        "proj:shape": [
+          10980,
+          10980
+        ],
+        "proj:transform": [
+          10,
+          0,
+          399960,
+          0,
+          -10,
+          4200000,
+          0,
+          0,
+          1
+        ]
+      },
+      "SCL": {
+        "title": "Scene Classification Map (SCL)",
+        "type": "image/tiff; application=geotiff; profile=cloud-optimized",
+        "roles": [
+          "data"
+        ],
+        "href": "https://sentinel-cogs.s3.us-west-2.amazonaws.com/sentinel-s2-l2a-cogs/33/S/VB/2021/2/S2B_33SVB_20210221_0_L2A/SCL.tif",
+        "proj:shape": [
+          5490,
+          5490
+        ],
+        "proj:transform": [
+          20,
+          0,
+          399960,
+          0,
+          -20,
+          4200000,
+          0,
+          0,
+          1
+        ]
+      },
+      "sir": {
+        "title": "Shortwave Infra-red",
+        "href": "https://maps.example.com/service/compose.tif?assets=B12,B8A,B11",
+        "virtual:hrefs": [
+          "#B12",
+          "#B8A",
+          "#B04"
+        ],
+        "roles": [
+          "sir",
+          "virtual"
+        ],
+        "gsd": 10,
+        "type": "image/tiff; application=geotiff; profile=cloud-optimized"
+      }
+    },
+    "links": [
+      {
+        "rel": "collection",
+        "href": "./collection.json",
+        "type": "application/json",
+        "title": "Sentinel-2 L2A Cogs Collection"
+      }
+    ]
+  }
\ No newline at end of file
diff --git a/tests/extensions/test_virtual_assets.py b/tests/extensions/test_virtual_assets.py
new file mode 100644
index 000000000..4adbdd24a
--- /dev/null
+++ b/tests/extensions/test_virtual_assets.py
@@ -0,0 +1,36 @@
+import json
+import logging
+from copy import deepcopy
+from datetime import datetime
+from typing import Any, Dict, List, cast, TypeVar
+
+import pytest
+from dateutil.parser import parse
+
+from pystac import Item
+from pystac.extensions.virtual_assets import VirtualAssetsExtension
+from tests.utils import TestCases
+
+logging.basicConfig(level=logging.DEBUG)
+logger = logging.getLogger()
+
+SENTINEL_ITEM_EXAMPLE_URI = TestCases.get_path(
+    "data-files/virtual-assets/sentinel-item.json"
+)
+
+@pytest.fixture
+def item_dict() -> Dict[str, Any]:
+    with open(SENTINEL_ITEM_EXAMPLE_URI) as f:
+        return cast(Dict[str, Any], json.load(f))
+
+@pytest.fixture
+def sentinel_item() -> Item:
+    return Item.from_file(SENTINEL_ITEM_EXAMPLE_URI)
+
+def test_stac_extensions(sentinel_item: Item) -> None:
+    assert VirtualAssetsExtension.has_extension(sentinel_item)
+
+def test_has_hrefs(sentinel_item: Item) -> None:
+    asset = sentinel_item.assets['sir']
+    assert VirtualAssetsExtension.ext(asset).hrefs == ['#B12', '#B8A', '#B04']
+