Gothenburg, Sweden, was built as a bastion fort [1]. When the fortifications were removed in the early 19th century, large parts of the ramparts were converted into a public park, which still surrounds the city center[2].
Also true for Utrecht in the Netherlands. They have just finished restoring the moat that goes around the inner city where the fortifications were. For several decades part of the moat was converted to a motorway. https://bicycledutch.wordpress.com/2020/09/09/cycling-around...
