Old Speck is flanked to the southwest by Mahoosuc Arm, and faces Baldpate Mountain to the northeast across Grafton Notch.

The southeast and southwest faces drain into the Bull Branch of Goose Eye Brook, then into the Sunday River and the Androscoggin.

The summit of Old Speck is on the southern boundary of Grafton Notch State Park.

Speck Pond is located below the mountain's summit, at 3,400 feet (1,000 m), it is stocked with brook trout.

[5] The Appalachian Trail descends 1.1 miles (1.8 km) from a location near the summit of Old Speck Mountain to the pond.