Montezuma National Wildlife Refuge preserves part of the historic Montezuma Swamp at the north end of Cayuga Lake, one of the largest contiguous wetland complexes in the northeastern United States. Along the Atlantic Flyway, it serves as a major stopover and nesting area for more than 300 bird species and supports mammals, reptiles, and amphibians in marsh, upland, and wooded wetland habitats. Although the marsh dates back more than 10,000 years and was inhabited early by Algonquin peoples and later the Cayugas, canal projects drained much of it by 1910. Federal restoration began in 1937, and the refuge opened in 1938; active management continues to sustain productive wetland habitat.