The Bourguillon Gate barred upper access to the Maigrauge loop and is the only part of the wall made of freestone and quarry stone. The tower was built in the middle of the fourteenth century and raised to a height 14 metres at the end of the sixteenth century.
To the east is a trench where the remains of an earlier wall are found.
The powder Tower exploded in 1737 and was not rebuilt. Built in the middle of the fourteenth century and heightened in 1420, the square shell gate tower had been made of tufa and sandstone and given a hipped roof in the sixteenth century.