From the longer Wikipedia page 
The Bridge House Estates is a charitable trust, established in 1282 by the City of London Corporation in London, England. It was originally established to maintain London Bridge and, subsequently, other bridges. Funded by bridge tolls and charitable donations, the trust acquired an extensive property portfolio which made it more than self-sufficient. As well as maintaining the bridges, the estates also makes other charitable grants through the City Bridge Trust, their grant-making arm. It is one of three funds managed by the City of London, the other two being the City Fund and the City's Cash.
The website is