4 days
Iceland is extremely safe and welcoming. Honestly, one of the coolest places I’ve been on the planet. Nothing else like it. The geography and ecology of that island is just cool as hell lol.
The people are all very kind and welcoming and it has a sort of communal vibe that is partly a mix of island and Scandinavian cultures. Awesome place and awesome people.
It is expensive. That is the only thing I would say is a drawback. For me, I think it is definitely worth it.
Iceland is an amazing place for both. I would consider Iceland to be more at the forefront of environmental science than Hungary, but I could be surprised.
Eastern Europe is a bit more wild and would be less my cup of tea, but if you’re mainly going for fun, that may be the better option.