Level 10+ should be fine. If you think you don't have enough experience you could go and do a few levels of Watchers Keep, if you can handle that you can handle Spellhold and beyond.
Well, obviously it depends on the classes, lvl11 cleric is equivalent to lvl14 bard for example, but if all your chars are lvl10 or above, you should be fine (I've just entered spellhold in my game too )
This has been covered before, and is still in our forum database. Please use the search mechanism to find it, and also to find various threads with hints of how to survive Spellhold.
Thread closed.
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