Sea Rim State Park occupies 4,141 acres on the Gulf of Mexico in southeastern Texas, where Gulf beach meets mainland marsh beside McFaddin National Wildlife Refuge. Acquired in 1972 and opened in 1977, it has been repeatedly shaped by erosion and hurricanes, including the 1989 destruction of Texas State Highway 87 through the park and major damage from Hurricanes Rita and Ike. The park includes a Beach unit on the Gulf and a Marsh unit with a cabin, boat launch, and paddling trails. Known for fishing, crabbing, alligators, and migratory birds, it offers access to an undeveloped stretch of Texas coast and a broader wetland system supporting more than 300 bird species.