Member institutions are located in the Mid-Atlantic states of Maryland, New Jersey, and Pennsylvania, and the national capital of Washington, D.C.

The first intra-conference competition was played on September 15, 2007, at Kings Point, New York, when the University of Scranton defeated the United States Merchant Marine Academy 2–1 in men's soccer.

On May 22, 2015, Merchant Marine announced that it accepted an invitation to rejoin the Skyline Conference—a league in which it had been a charter member—effective the 2016–17 school year.

[3] On April 1, 2022, Keystone College was announced to be joining the Landmark Conference as an associate member in football starting in the 2023-24 season.

The logo submitted by Susquehanna University's graphic design major, Manor member, and men's lacrosse player Tim Storck ’08, of Cockeysville, Maryland, was selected.