ToME Wiki
Moria
The Mines of Moria span dungeon levels 30 to 50.
Terrain: Background: mountains. Granite-lined rooms are mostly rectangular, with one-square-wide paths through the mountains.
Monsters: Orc-types (orcs, uruks, trolls, ogres, etc.), zephyr hounds, undead, and a smattering of other monsters.
Boss: The bottom level of Moria is guarded by Durin's Bane, the Balrog of Moria.
Special levels and features
Level 35 of Moria is a non-persistent special level, the Orc Town.
At level 40, you will find entries (via purple '>') to the Small Water Cave.
At the bottom of Moria, you can take another purple '>' to travel to the dwarf town of Khazad-dum.
Word of Recall
Because of the access to Khazad-dum, Moria is unusual with regard to recall. If you travel past the bottom level of Moria to the town of Khazad-dum through the dark caves, you will not be able to recall directly out.
Chatter
PaulMoore: "Moria is buggy with regard to recall". Too right. I am using 2.3.2, and I got to the end of Moria and out to Khazad-dum. Nothing much there, so I want to go home. Back to the dungeon (I didn't make the mistake of recalling to the dungeon, as that would reset my recall point - clever me, or so I thought... 
) But recall then took me back to ... Khazad-dum! And from there, recall takes me back to Moria. Stuck, with no way back out of the mountains except for slogging through Moria again 
Is this a manifestation of the bugginess referred to above, or did I do something wrong? If it is a bug, is it worth raising a bug report, or is it something known that I just have to live with?
(As it happens, I had a quick way out via Probability Travel, floating up through the levels, but I was pretty fed up there for a while. I hate Moria...)
NeilStevens: Actually, the bugginess was fixed in 2.3. The current behavior is the intended behavior. Getting out of Moria isn't easy. Ask Gandalf.
"Happiest Sadist" Just bring a scroll of Reset Recall (preferably fireproof). Reset your recall depth to the first level of moria. Then when you recall you will be standing on the tairs that lead to the outside.
Derakon: This might be my imagination, but monsters seem to be either much more alert or much more spawn-happy in Moria than in other dungeons. This gives the impression of continually being under siege and rarely having a chance to rest. Maybe it's just that there's so much loot to sort through and identify (since orcs, etc. mostly drop weapons and armor).
ZizzoTheInfinite: It's not your imagination; Moria has a much higher monster generation rate than any other dungeon. I've frequently run into newly generated monsters in rooms I literally just got through clearing a few minutes before.