Originally, the Pool of London was the stretch of the River Thames forming the south side of the City of London. The term was later used more generally to refer to the stretch of the river in between London Bridge and Rotherhithe, which constituted the furthest reach that could be reached by a tall-masted vessel. It therefore became a key part of the Port of London. In order that access to the Pool for shipping was not obstructed a new pedestrian connection between Rotherhithe and Wapping was constructed not as a new bridge but as a tunnel.
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