Mount Castor Marsh Conservation Area is a 40-acre wetland preserve. The conservation area is open to the public for hiking, birdwatching, and nature photography. The trails are well-maintained and offer scenic views of the marsh and the surrounding forest. The conservation area is managed by the Amherst Conservation Commission, which aims to protect and enhance the natural resources of the town. 

Mount Castor Marsh Conservation Area contains a portion of the K.C. Trail and Mount Castor. Trail access is from Valley View Drive.