Mercer’s Mill Covered Bridge, also known as Mercer’s Ford Covered Bridge and officially called East Octoraro #2 Bridge, carries Bailey Crossroads Road over the East Branch of Octoraro Creek on the Lancaster-Chester county line near Christiana in southeastern Pennsylvania. Built in 1880 by B. J. Carter, it is a surviving example of late 19th-century rural bridge building and part of Pennsylvania’s timber-bridge tradition. The single-span wooden bridge uses double Burr arch trusses with steel hanger rods, has an oak-plank deck, and retains the red paint and white approaches typical of Lancaster County covered bridges. It was listed on the National Register of Historic Places in 1980.