The Museum of Cosmonautics is Zhytomyr's best-known museum and the clearest reason to stop in the city. It is dedicated to Sergei Korolyov, the Zhytomyr-born engineer who became one of the main figures behind the early Soviet space programme.
The museum combines biographical material with spacecraft models, equipment, and Cold War space-race context. Even if you are not a space obsessive, it gives Zhytomyr a specific story that few Ukrainian cities can match.