I don't know about Berlin but I do know about Vienna. My recollection is that we were on the Austrian border and stayed there for about a week. We had gone from Munich/Dachau is a few days and there was no reason/opposition to wait. We could easily have gone to Vienna but as we found out later, Roosevelt had made arrangements with Stalin. Roosevelt had a lot of Commie lovers in his administration. The Russians were even supplied with our currency plates.
There's a huge, ugly Russian built bridge in Vienna. They also have the West Bahn Hof, a nice place built by the Western Allies about the same time as that bridge. The old central bahn hof was located in the Russian zone.