The Chesapeake Bay is about 200 miles (300 km) long, from the Susquehanna River in the north to the Atlantic Ocean. At its narrowest point between Kent County's Plum Point (near Newtown) and the Harford County shore near Romney Creek, the bay isabout 2.8 miles (4.5 km) wide. At the widest location, it is 30 miles (50 km) wide. The bay is deep on average.