Located off Lowell Road in Concord, Old Calf Pasture offers a boat launch and short riverside trail ending at the confluence where the Assabet and Sudbury Rivers join to form the Concord River.

The site is ideal for picnicking along the riverbanks and provides access for paddlers and anglers, though visitors should be aware that the area is subject to flooding.

Across the river lies Egg Rock, a local landmark accessible via a separate trail off Nashawtuc Road.