ToME: the Tales of Maj'Eyal

I wasted the Bearscape recently by withdrawing my character, this lvl15 alchemist proved a bit too weak to face the bears. Moving back to the world map closed the portal.
I'd like to avoid the same mistake with the portal to the Lost Land of Poosh and I was wandering what minimum level I should have to go there ?

I'd say about 15, depending on your equipment and build. Worst case scenario is you get a rare/unique mature dragon spawned with some nasty talents (or 2 at the same time). On normal difficulty you're just mowing down the swarms of hatchlings and other animals. Boss isn't too bad unless you're unlucky.

I find the boss can be quite tricky, with all the status effects that he will unload upon you (maybe I am thinking of nightmare difficulty). I would say 15 is the lowest level that you would want to go there at, a bit higher is better.