Mint Street is simply the space bounded between the two walls of the Tower of London, it is a narrow street and seems not to be one and yet there are sometimes cars running there! It must be said that the street serves various houses located against the ramparts. Besides, Isaac Newton lived in these houses for a while.
Beginning just behind the Byward Tower, ie the entrance to the monument, it stretches along the entire length of the outer rampart and continues behind the North rampart and its inhabited casemates. It is probably the people who use it. The Rue Mint leads, from the beginning, to two casemates, on the left: They shelter a permanent exhibition of coins, fairly interesting exhibition.
There is not much to say about this particularity of the Tower of London except that you can walk around it, but it feels like you're off the beaten path.
The map of the tower of London with the list of the buildings