One Tree Hill is a 7 hectare public park, local nature reserve and Site of Borough Importance for Nature Conservation, Grade 1, in Honor Oak in the London Borough of Southwark. It is owned and managed by Southwark Council.
One Tree Hill is named after the Oak of Honour which marked the southern boundary of the Norman Honour of Gloucester. It was later owned by the Abbots of Bermondsey, until it was confiscated by the monarchy during the Dissolution of the Monasteries. According to legend, Queen Elizabeth I rested under an oak at the summit on her way to visit Lewisham in 1602. The current oak (pictured above) is the third on the site, planted in 1905.
Before the end of the eighteenth century, the East India Company built a semaphore station on the top of the hill to signal when ships were sighted in the Channel, and it was used as a beacon point by the Admiralty during the Napoleonic Wars. In 1896 the hill was fenced off by a local golf club, but this led to large scale protests and trespasses, and in 1905 the site was compulsorily purchased by the new Camberwell Borough Council. The church of St Augustine was built on the north-east side of the hill between 1872 and 1900. It is fenced off from the public park. In 1957 John Betjeman described the view from the top as “better than that from Parliament Hill”.
The steep hill is wooded with open grassland at the top. The site has many ancient trees, but the main ones are hybrid black-poplar and London plane, the result of former landscaping. There are also wild service trees and midland hawthorns. The ground flora includes bluebells, heath grass and compact rush.
There is access from Honor Oak Park and Brenchley Gardens.