Gate 52 is a seemingly insignificant trailhead that leads down to an area of historic interest. During WWII, parts of the Quabbin were used by the military. The Quabbin Reservation had been created and was off limits to the public, but the water had only just started filling in, so much of the land was still exposed. The U.S. Air Force would use the valley floor for target practice with dummy bombs (often filled with flour). The end of the road from Gate 52 was used as a practice shooting range. Concrete structures were built here to store the ammunition, and there was also a helicopter landing pad. The remains of these structures can still be seen.

The Quabbin Reservoir is a remarkable engineering feat that provides water to millions of people in Massachusetts. It was constructed in the 1930s by damming the Swift River and flooding four towns in the process. The reservoir covers an area of 39 square miles and has a capacity of 412 billion gallons. The Quabbin Reservoir is a popular destination for fishing, hiking, and wildlife viewing. The reservoir is surrounded by a protected forest that hosts a variety of plants and animals, some of which are rare or endangered. 

Quabbin Reservoir is one of the largest unfiltered water supplies in the United States. Along with the Wachusett Reservoir and Ware River, it is the source of high-quality water for the Massachusetts Water Resources Authority water supply system. Recreational activities are regulated and limited to protect 3 million people’s drinking water.