and intense, widespread rainfall from coastal hurricanes and tropical storms, flood the island more deeply several times a century. The island's vegetation is quite diverse for a relatively small area, due to its geological and topographic variety, the frequency of floods, its land-use history (including various periods of landscaping), and its location in an urban area in which many non-native species occur. Most of the island is deciduous forest of various kinds, including uplands, riparian shores, and swamps. There is also an area of fresh-water tidal (estuarine) marsh, and a few small bedrock outcrops of metamorphic Piedmont rock, some along the tidal shore. The variety of freshwater estuarine intertidal habitats along the island's shores is particularly notable. The island is particularly known for its variety of birds and its showy displays of spring wildflowers. However, dozens of non-native invasive plants have become abundant there, often outcompeting the native species. Access Theodore Roosevelt Island is accessible by a footbridge from a parking lot along the Virginia bank of the Potomac River, just north of the Theodore Roosevelt Bridge, which crosses but does not allow access to the island. Cars can enter this parking lot only from the northbound lanes of the George Washington Memorial Parkway. Pedestrians can reach the parking lot and footbridge by following the Mount Vernon Trail south from the intersection of Langston Boulevard and North Lynn Street in Rosslyn, near Key Bridge. The closest Washington Metro station to the island is the Rosslyn station. Several hiking trails provide access to the memorial and a variety of the island's natural habitats, including a boardwalk through a swampy and marshy area. In popular culture A story by Ernest Seton Thompson "The Royal Analostan" mentions the island as the origin of the fictional cat breed. The 2014 movie Captain America: The Winter Soldier depicted Little Island as the site of the Triskelion, the headquarters of the fictional S.H.I.E.L.D. spy agency. In 2019 video game Tom Clancy's The Division 2 the island was the site of a failed quarantine effort after the outbreak of a manufactured epidemic disease. The citizens quarantined on the island radicalized into a group called the "Outcasts", one of the game's major antagonist factions. See also List of national memorials of the United States List of islands of the United States List of islands on the Potomac River List of sculptures of presidents of the United States Presidential