Trappe is a borough in Montgomery County, Pennsylvania, United States. The population was 3,509 at the 2010 census. Augustus Lutheran Church, built in 1743, is the oldest unchanged Lutheran church building in the United States in continuous use by the same congregation. It has been designated a National Historic Landmark.
Trappe is located at 40°11′50″N 75°28′31″W / 40.19722°N 75.47528°W / 40.19722; -75.47528 (40.197111, -75.475244).
According to the United States Census Bureau, the borough has a total area of 2.1 square miles (5.4 km²), all of it land.