Walden Ponds Wildlife Habitat is a 102-acre protected area in Boulder County, Colorado, created from an exhausted open-pit gravel mine west of 75th Street between Jay Road and Valmont Road. Reclaimed between 1974 and the 1990s, the site was transformed from stripped bedrock, pits, and groundwater puddles into ponds, marshes, and trails for wildlife and public recreation. Named for Boulder County commissioner Walden “Wally” Toevs, who pushed to restore the land, it is now known as one of the county’s best bird-watching areas. Linked by trails to nearby Sawhill Ponds, the broader wetland landscape has recorded 300 bird species.