I'm trying but it's gonna be difficult with a road network so perfect.
Anyway, depending on how you're willing to stray:
- Frankfur Am Main is the best fit i found, if you add/ignore the bastion w/walled area on the other side (source)
- Aosta is really good too, except the big river is a bit further away. Roman founded cities built by a river are good candidates because of the square-shaped castra they were built around.
- Milan has a lateral citadel like your map, with no river/harbour by it and a circular rather than square shape, but lots of canals. The internal circle is the edge of the Gaelic and then Roman city (not founded by Romans, so no square city centre). Map linked is late and showing modern Italian style (post-firearm) fortifications.
- I have no literature here, but I suggest you check fortress and cities built by the Teutonic Knights on rivers in Prussia. Osprey publishes two books on "Crusader Castles of the Teutonic Knights" that might be helpfful.
- London, as also RSConley mentions, is probably the best fit. It also has a citadel quite close to the river :) (two maps here)