This is Reference Mark No. 1 for station MY4112--PROSPECT HINGHAM, located at the peak of Prospect Hill in Wompatuck State park, Hingham, MA. This is a brass disk, about 3.5 in. in diameter, set in the top of a 12-inch square concrete monument. The arrow points towards the station, which is just over 256 ft. distant (an unusually long distance for a reference mark; most are within 30 ft. of their stations). The PROSPECT HINGHAM station is unusual for another reason: there were a total of six reference marks set for it.