was fortified by the Round Tower, the Square Tower, Southsea Castle, Lumps Fort and Fort Cumberland. Four sea forts were built in the Solent by Lord Palmerston: Spitbank Fort, St Helens Fort, Horse Sand Fort and No Man's Land Fort. The resort of Southsea is on the central southern shoreline of Portsea Island, and Eastney is east. Eastney Lake covered nearly in 1626. North of Eastney is the residential Milton and an area of reclaimed land known as Milton Common (formerly Milton Lake), a "flat scrubby land with a series of freshwater lakes". Further north on the east coast is Baffins, with the Great Salterns recreation ground and golf course around Portsmouth College. The Hilsea Lines are a series of defunct fortifications on the island's north coast, bordering Portsbridge Creek and the mainland. Portsdown Hill dominates the skyline in the north, and contains several large Palmerston Forts such as Fort Fareham, Fort Wallington, Fort Nelson, Fort Southwick, Fort Widley, and Fort Purbrook. Portsdown Hill is a large band of chalk; the rest of Portsea Island is composed of layers of London Clay and sand (part of the Bagshot Formation), formed principally during the Eocene. Northern areas of the city include Stamshaw, Hilsea and Copnor, Cosham, Drayton, Farlington, Paulsgrove and Port Solent. Other districts include North End and Fratton. The west of the city contains council estates, such as Buckland, Landport, and Portsea, which replaced Victorian terraces destroyed by Second World War bombing. After the war, the Leigh Park estate was built to address the chronic housing shortage during post-war reconstruction. Although the estate has been under the jurisdiction of Havant Borough Council since the early 2000s, Portsmouth City Council remains its landlord (the borough's largest landowner). The city's main station, Portsmouth and Southsea railway station, is in the city centre near the Guildhall and the civic offices. South of the Guildhall is Guildhall Walk, with a number of pubs and clubs. The city's other railway station, Portsmouth Harbour railway station, is located on a pier at the harbour's edge, near Old Portsmouth. Edinburgh Road contains the city's Roman Catholic cathedral and Victoria Park, a park which opened in 1878. Climate Portsmouth has a mild oceanic climate, with more sunshine than most of the British Isles. Frosts are light and short-lived and snow quite rare in winter, with temperatures rarely dropping below freezing. The average maximum temperature in January is ,