The Imperial National Wildlife Refuge protects wildlife habitat along 30 miles (50 km) of the lower Colorado River in Arizona and California, including the last un-channeled section before the river enters Mexico. The Imperial Refuge Wilderness, a federally designated, 15,056-acre (60.93 km2), wilderness area is protected within the refuge. It also surrounds the Picacho State Recreation Area. This section of the Colorado River is popular for boating, hiking, fishing, camping, exploring old mining camps and wildlife watching.