Should not be confused with Rounds Mountain, also located in Massachusetts.

Round Mountain, 2,296 feet (700 m), located on the border of southwest Massachusetts and northwest Connecticut, is a prominent peak of the Taconic Range. The peak and southern slopes of the mountain are within Connecticut; the northern slope lies within Massachusetts.

Round Mountain
Summit of Round Mountain
Highest point
Elevation	2,296 ft (700 m)
Coordinates	42°02′56″N 73°28′35″W / 42.04889°N 73.47639°W / 42.04889; -73.47639
Geography
Location	Mount Washington, Massachusetts and Salisbury, Connecticut
Parent range	Taconic Mountains
Geology
Age of rock	Ordovician
Mountain type	Thrust fault; metamorphic rock and sedimentary rock
Climbing
Easiest route	Mount Frissel Trail

The mountain is located within the towns of Mount Washington, Massachusetts and Salisbury, Connecticut; much of it has been conserved as part of Massachusetts' Mount Washington State Forest and Connecticut's Mount Riga Forest Preserve. The south side of Round Mountain drains into Riga Lake and South Pond, then into Wachocostinook Brook, Salmon Creek, the Housatonic River, and Long Island Sound. The north side drains into Sages Ravine, thence into Schenob Brook, the Housatonic River, and Long Island Sound. Round Mountain is bordered by Mount Frissell to the northwest, Mount Ashley to the north, and Bear Mountain to the east.

Round Mountain is traversed by the Mount Frissell Trail which connects with the South Taconic Trail to the west and the Appalachian Trail to the east.