It's more of a "City with some walls" and it's rightly on the endanger list because urban development has made it seem like there are just remains and ruins in-between a modern city. It's not horrible in any way but I wouldn't call it a marvel of culture to be placed on the world heritage list.

Anyone coming to Azerbaijan is probably gonna set foot in Baku. It's the gateway to the country and the only thing you could avoid is the city center. The airport is a bit out of town and after you drive and marvel at the modern skyscrapers that reminded me off Dubai, built by gas money for sure, you can set foot in a sort of old town. There aren't many special things to see. The tower as seen twice in my pics is probably the biggest thing. Trotting around will take less than an hour and you will feel "oh it's another brick wall" here and there - nothing major. You find street peddlers, shops, food bazaars and it's all pretty enjoyable. As I said it's nothing bad and a stopover in Baku is easy and probably on the average Joe/Jane's itinerary anyway so just don't expect too much.

p.s. not sure how it is these days but as you can see from my pic I visited in 2017 and Google Maps didn't allow navigation so be prepared for alternatives if you want a drive app running (Waze probably works better).