It's an amazing place.
It is best to put 1.5 days on excursions. You can manage it in a day, but you will have to gain strength because there are many objects and they are all interesting. You can enter the fortress itself for free through a checkpoint with car entrances (there are 2 of 4 of them). If you want to go inside each museum, you need to purchase a single ticket for 200 thousand sums from the outside. (~1,500 rubles. for April 2024). Without a guide and an organized tour, it may not be so interesting and monotonous. It is better to take a guide, of course. In the evening, beautiful illumination of ancient architecture. The restaurants inside the fortress are expensive and not all of them are of good quality. I do not recommend visiting the Terrace restaurants (there are two of them).
The old town is located inside the fortress walls. Not a single modern building, everything is historical. You get to the time of the Khorezm Khanate. There are a lot of workshops, souvenir shops, a huge selection of souvenirs made in Uzbekistan (shawls, scarves, bathrobes, dresses, magnets, postcards, mystery boxes, canes, book stands, skullcaps, sweets, ceramic tableware and much more. Not made in China, but local craftsmen. And the plan to eat is a teahouse on a teahouse, a restaurant on a restaurant, a large selection, reasonable prices. A museum on a museum, a lot of madrassas that you can go to, the Juma mosque is a separate story (but either read about it beforehand, or take a guide to understand where you got to at all), a stunningly interesting silk museum opened a month ago (there are also workshops on creating and dyeing silk, weaving carpet, tea party and sooooo interesting excursion). There are many hotels right in the center, so you don't even have to go outside the fortress wall. In the evening, the lights turn on and the city becomes absolutely magical.
I recommend you to visit. What surprised me the most was that people live inside the fortress. There are streets with house numbers. It is essentially a city within a city.
Inside the fortress itself there are hotels and guest houses where you can stay overnight.
The ticket costs 100,000 soums, it opens access to all museums, but you will have to pay an additional 15,000 soums for climbing the minaret (whose height is 56 m). Inside there are also cafes where you can eat, choyhon, souvenir shops.