Vienna
Vienna is the top thing to see while in Bratislava.
I think Vienna is how people from my country imagine the EU: clean, safe, modern and full of beautiful squares and parks. The city is stylish. It nicely blends modern design and classical elegance.
I explored the city by bike (just €1,50/h) and cycled along the Danube.
Metro and train stations have a brutalist vibe.
I went to the airport by bike, drinking radler along the way, fully embracing the European lifestyle. It is 20km away from the city centre. There is a path, but it is dark at night.