The First Parish Church of Stow & Acton is located at 353 Great Road (Route 117) in Stow, Massachusetts - where Route 62 turns toward Hudson - at the set of traffic lights. (Randall Library is on one side of First Parish; the Union Church is on the other).
When coming from Route 495, take Exit 27 towards Stow. Drive about five miles and you will see First Parish on your left just after the lights. (First Parish is the white church with dark green front doors).
If you are coming from Route 95 (128), take Exit 26 for Waltham (Route 20). Route 20 forks right; stay in left lane and take next left to get on Route 117. Stow will be about 14 miles from that point and the church will be on your right.