It’s older than the oldest Puritan meetinghouse in Massachusetts. It’s older than the oldest Episcopalian chapel in Jamestown, Virginia. In fact, it’s the oldest American church of any denomination, period.
It’s the San Miguel Mission in Santa Fe, New Mexico.
Founded in 1610, ten years before the Mayflower landed at Plymouth Rock, the San Miguel Chapel is a Spanish colonial mission whose original adobe walls are still standing.