The Port of Liverpool is the enclosed 7.5 miles (12.1 km) dock system that runs from Brunswick Dock in Liverpool to Seaforth Dock, Seaforth, on the east side of the River Mersey and the Birkenhead Docks between Birkenhead and Wallasey on the west side of the river. The port is being extended by the building of an in-river container terminal at Seaforth Dock, name Liverpool2. The terminal will berth two 14,000 container Post-Panamax ships.