Completion of the First Dry Dock

1496

The dry dock ordered by Henry VII was completed around 1496, making Portsmouth home to one of the earliest purpose-built dry docks in European naval history. A dry dock allows a vessel to be brought in on a high tide and then sealed so that the water can be pumped or drained out, leaving the ship's hull fully exposed for inspection, cleaning and repair. Before the development of dry docks, ships had to be careened, that is, hauled onto their sides on a beach or slipway, a laborious and potentially damaging process. The Portsmouth dry dock was constructed using timber and incorporated a gate system to control the water level. Its construction required considerable skill and investment, and its success encouraged further development of the dockyard facilities. The dock was located near the present site of the Historic Dockyard and established the pattern of industrial activity that would continue on this waterfront for over five hundred years. The engineering principles demonstrated at Portsmouth influenced the design of subsequent dry docks at other naval yards. The dock also attracted skilled shipwrights and associated tradesmen to the area, beginning the process by which Portsea would grow into a densely populated dockyard community.