We took a train across the river from Vienna to Bratislava, Slovakia, which only took one hour. They are the closest capital cities of two countries in the world.
This is an awesome city, we were only there for 2 days but that was plenty of time to explore & see all of the city (it is not very big). We visited a medieval faire at the old castle by the river and did some axe throwing and archery, drank some “Kofola” (like cola and beer mixed together), and ate traditional Slovakian food – very cheesy. The best thing about Bratislava is that it is so so cheap! It’s a really cool place.