Nestled in the heart of Lewistown, along the Juniata River in Mifflin County, St. Mark's Episcopal Church is one of the oldest parishes in the Episcopal Diocese of Central Pennsylvania and has served the people of the Lewistown area for almost 200 years.  Located near the geographic center of the state, the area became a hub for traffic moving in every direction as Mifflin County became the crossroads of the Commonwealth.  Lewistown's character as a crossroads community has informed St. Mark's Parish as a place of discovery and a community open to all.

St. Mark's is the only Episcopal Church in Mifflin County.  The first Episcopal Congregation in Lewistown was formed in 1818.  In 1820, Episcopalians began meeting in a one-room log courthouse in the town square.  In 1824, the first church was built on Main Street, just off the Square.