Portsmouth (ⁱ/ˈpɔːtsməθ/) is the second largest city in the ceremonial county of Hampshire on the south coast of England. Portsmouth is notable for being the United Kingdom's only island city; it is located mainly on Portsea Island. It is situated 64 miles (103 km) south west from London and 19 miles (31 km) south east of Southampton.

As a significant naval port for centuries, Portsmouth is home to the world's oldest dry dock still in use and also home to some famous ships, including HMS Warrior, the Tudor carrack Mary Rose and Lord Nelson's flagship, HMS Victory. Although smaller than in its heyday, the naval base remains a major dockyard and base for the Royal Navy and Royal Marine Commandos whose Headquarters resides there. There is also a thriving commercial ferryport serving destinations on the continent for freight and passenger traffic. The City of Portsmouth and Portsmouth Football Club are both nicknamed Pompey.