Then how about you choose a safe place and a dangerous place? Come on man, show us what you got!
The best I can do is name a few, since I really don't think I'm even capable of narrowing it down to just one. I'm... indecisive. ^^;
Marbule from Chrono Cross. Assuming I could fit in socially, it's super cozy and beautiful, with lots of places to swim and relax. It also has a dragon. :D
Water Park from Mario Kart 8. It's a water-themed amusement park that heavily uses the water for the rides, including a fully underwater trolley and an underwater coaster.
Shrine of Amana. Truly one of the most beautiful locations I've ever seen in a video game, and with such a soothing atmosphere. Sure... it's full of hostile undead trying to kill you from every direction, but other than that...
Water Dimension (Terrestrial Plane). There's something about this place that's always been extremely captivating to me, even comforting. True, it's incredibly hostile and full of monsters, and there's no sign of peaceful life anywhere... but that's beside the point.
Sunken City in Dracula X. This is sort of a cheat and goes along with the Water Dimension, but essentially any grand stone city that is either heavily flooded or entirely underwater. I love how flooded stone ruins look and the atmosphere they have, it's just so captivating and beautiful.
There's so many other things I could list and nothing I can really feel too definitive of. If I thought about it long enough these five might not even make the list. @.@ But I'll stand by them.