Do not miss spending several hours at the Szechenyi Baths in Budapest. It couldn’t be easier to get there - just take Metro 1 towards Mexikoi Ut, and get off at Széchenyi fürdő. You’ll see the large yellow buildings as soon as you pop above ground.
Budget at least 3 hours - it’s a huge complex full of a variety of saunas, steam rooms and beautiful indoor and outdoor baths to explore. Don’t forget flip-flops and water. And you’ll be even happier if you also take sandwiches, a robe and perhaps a can of beer. Also, don’t miss the super hot downstairs saunas, accessed only from outside, and make sure you cold plunge after!
Jeez, I am bossy.