The center of the town is the Cross Keys Inn (Cross Keys Tavern) that was established there on the old Post Road (which is now Calvert Road) in 1774. The Post Road was the main road that ran in between Philadelphia and Baltimore during Revolutionary times. Directly next to the Cross Keys Inn (which is now a private brick residence), is the Calvert Elementary School, operated by Cecil County Public Schools.
The main historical reference in Calvert is the "East Nottingham Friends House" at this intersection. William Smallwood, a general during the Revolutionary War, used this building as a hospital for a short time in 1778, and several soldiers who died at the hospital are buried on its grounds.