is a borough in Beaver County in Western Pennsylvania, incorporated in 1905 and named after the American Bridge Company. Ambridge is located 16 miles (25 km) northwest of Pittsburgh, alongside the Ohio River. In 1910, 5,205 people lived in Ambridge; in 1920, 12,730 people lived there, and in 1940, 18,968 people resided in Ambridge. The population was 7,769 at the 2000 census.
According to the United States Census Bureau, the borough has a total area of 1.7 square miles (4.4 km²), of which, 1.5 square miles (3.8 km²) of it is land and 0.2 square miles (0.6 km²) of it (12.87%) is water.