Rehoboth Church in Monroe County is claimed to be the oldest church building west of the Allegheny Mountains. The church, listed on the National Register of Historic Places, lies two miles east of Union on State Route 3.

About 1786, Edward Keenan, who had converted to Methodism from Catholicism, deeded five acres for the church and burying grounds. The beginning of an independent American Methodist Church had occurred only a few years before. Tradition says that Francis Asbury preached the Rehoboth dedication sermon as he stood in the church's doorway because the crowd was too large for the small structure. Asbury also held sessions of the Greenbrier Conference at Rehoboth in 1792, 1793, and 1796.

Rehoboth Church is made of logs hewn on the inside only. The inside measures 21 feet by 30 feet, and the walls to the eaves are 13 logs high. The building's only door is 40 inches wide and only 65 inches high. The church has a window on the east end, located behind the pulpit to provide light for reading, and a larger window on the north side. A pulpit of rough-hewn walnut and poplar boards stands high against the east wall to give the preacher a good view of the worshipers in the balcony, and some of the backless puncheon benches used by Rehoboth's early congregations are still in place.

Rehoboth Church still stands where it was built. The Rehoboth Museum Center contains several artifacts from the region, including a communion table from the church.