Bridge House Estates is a fund administered by the City of London. It was established by Royal Charter in 1282 when finance was needed to build and maintain Old London Bridge. Its income was initially generated through bridge tolls, taxes levied on goods transported over London Bridge and from properties that once lined the river crossing. Today, Bridge House Estates maintains the five bridges crossing the Thames into the Square Mile, namely Tower Bridge, Blackfriars Bridge, Southwark Bridge, London Bridge and Millennium Bridge. It also operates City Bridge Trust which manages the surplus funds accumulated since its foundation. The Trust supports a vast range of charitable causes, environmental initiatives and social investment across Greater London.