Geograph - photograph every grid square

Grade I listed buildings and structures are of exceptional, even international importance. There are over 6,000 in the country. Only 2.5% of listed buildings are Grade I listed.
In Scotland the classification is Category A
Index: Link

Originally there were only four entrances (or Gates) into the walled city i.e. Bishop's Gate, Shipquay Gate, Ferryquay Gate and Butcher's Gate - arranged in a cross pattern with the Diamond as its centre. Later were added New Gate (1789), Castle Gate (1803) and Magazine Gate (1865). The original Gates were themselves re-built in the 18th and 19th centuries.