River Thames Thames Estuary), the river is subject to tidal activity from the North Sea. Before the lock was installed, the river was tidal as far as Staines, about upstream. London, capital of Roman Britain, was established on two hills, now known as Cornhill and Ludgate Hill. These provided a firm base for a trading centre at the lowest possible point on the Thames. A river crossing was built at the site of London Bridge. London Bridge is now used as the basis for published tide tables giving the times of high tide. High tide reaches Putney about 30 minutes later than
Queen Elizabeth II High School St John's. During the time the school has been opened it has gone under extensive changes and has dramatically increased in size and with this, one new building was opened in 2000, the Forster building, which is home to the sixth form. Then in 2007 building started on the Deans building which was to become the new home for the English Department on the upper floor, and the Music and performance area on the ground floor, this extension also provided the school with a much needed second dining room. Queen Elizabeth II High School Queen Elizabeth II High School (commonly