Please answer the following question: Zion Reformed United Church of Christ -  Zion Reformed United Church of Christ originally The German Reformed Church was founded in 1770 in Hagerstown Maryland. The church at 201 North Potomac Street was the first within the town limits. It is the oldest church building in Washington County Maryland that has been in continuous use as a church since its construction. During the American Civil War the church’s bell tower was used as a lookout by Union troops under the command of General George Custer. Given a choice of categories company, educational institution, artist, athlete, office holder, mean of transportation, building, natural place, village, animal, plant, album, film or written work, the text refers to which one?
A:
Building