St. Mark's is located in the Southwest Baltimore neighborhood of Morrell Park.  From Interstate 95, take the Caton Ave. exit, which is one exit north of 695 and several exits south of the tunnel.  Go south on Caton Avenue and go about half a mile.  Turn left on Washington Blvd, and follow it about three-quarters of a mile.  Turn left on Wickes Avenue (the same street as the Dunkin' Donuts).  We will be on your right.  Be sure to park facing the correct direction.

For more detailed directions, see this map.