Nethack: list of visited levels

This does not exist normally.

It does not exist in wizard mode either, but there is a similar command: Ctrl+o will show the locations of all special levels in the game (quest portal, Vlad's tower, etc.). Furthermore, levelporting with Ctrl+v and entering ? in the prompt for what level to teleport to will give you a similar list.

If you're playing on NAO and you want to check where Minetown is, for example, you can look up the ttyrec of your last game, play it back with a program such as ipbt, and use /string to search for an arbitrary string. More information on how to control playback is available in the "Playing" section of the online manpage.

I've developed a cheatsheet system that works pretty well for this. I start off with a scrap of paper that lists the important starting info.

Name Alignment/Gender/Race/Role (Spellcasting Attribute) Shorthand-Intrinsics

For names, I use letter progression;a,b,...z,aa,ab,... I got tired of dreaming up names long ago A/G/R/R has a shorthand such as L/N/C , 1st three letters of Race and Race/Role The Spellcasting Attribute is Int for Arc, Bar, Cav, Ran, Rog, Sam, Tou, Wiz Wis for Hea, Kni, Mon, Pri, Val

Intrisics CR, PR, FR, SLR, SHR, DisR, VFast, INV/SEE, ESP, Warn, FrAct, etc
I don't usually list Extrinsics other than VFast (speedboots), nor individual attribute levels because they can be id'd readily in game. If the character starts or receives Intrinsics by leveling up, I jot the first few potentials in along with a note of XL is needed. Then I just list what I get as I go (leave a bit of space, this list can get long).

Then it's just a matter of keeping notes about IMPORTANT things on each level, and TTDs.