The City of London has barely changed its borders in centuries and still follows the line of the old city walls to a great degree. The walls around the city, originally built by the Romans, have largely disappeared but several vestiges are still visible (notably outside the Museum of London; just near the Tower of London; and running part of the way down Noble Street) and various place names and streets hint at their prior existence. Locations such as Aldgate, Bishopsgate, Ludgate and Moorgate are the sites of old gates in the city walls.
The City of London is not a London borough and has an ancient and unusual local governance, with rights and privileges greater than those of anywhere else in the United Kingdom. The local authority is the City of London Corporation and the chief position is the Lord Mayor.
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