When was Gandalf in Moria?

[Formendacil]

Originally Posted by Mänwë

I would alert you to the fact that Aragorn did indeed also pass through Moria before their eventful and tragic passage.

"`I too once passed the Dimrill Gate,' said Aragorn quietly; 'but though I also came out again, the memory is very evil. I do not wish to enter Moria a second time.'" - Book II Chapter 4, A Journey in the Dark

He does not elaborate on what he experienced, but it is obviously sufficient enough to dissuage him from the want to enter again. Consequently he knew of something rather evil.

If one wants to pedantic... and since you seem the pedantic sort, I'll permit myself the amusement thereof, it simply says that Aragorn entered Moria- it does not say that he passed THROUGH Moria. To poke one's head through the gate and decide that it's a very nasty place, as Dáin did and presumeably as Aragorn did, is bold enough in the context of Moria, but isn't QUITE the same as Gandalf's trek THROUGH Moria.