The October Mountain State Forest is a state park and recreation area in Lee, Massachusetts. It is noted for being the largest state forest in all of Massachusetts.

Covering more than sixteen thousand acres, the October Mountain State Forest offers a lot of things to see and enjoy. For one, recreation here is excellent, as there are tons of things to do. Visitors can easily enjoy camping, boating, fishing, hiking, mountain biking, and even cross country skiing during the winter months. There are also opportunities for hunting (with a good amount of restrictions, of course). Off road vehicles are also welcome at the park.

The October Mountain State Forest got its name from Herman Melville, the famous author. He gave the site its name because of its stunning fall foliage.