I've played long Risk games, but the longest gaming sessions were the Civilization board game (this was long before the first computer game).
There were some of us in the local SCA group who were into board gaming, so we'd get together for Civilization, Eurorails (or some other variant of the Mayfair rail games), or another that took several hours. One thing I remember fondly about the Civilization games is that we would roleplay the diplomatic treaties and negotiations (that basically amounted to "I won't invade you if you don't invade me" or "let's be allies and invade _____ and divvy up their territories"). So when the guy playing Crete turned to me and said, "Noble Illyria (the territory I was controlling), I have a proposition for you..." I knew that he was making a proposition to ally in some invasion of another player. In the trading round, there were disaster cards we could slip in with the shipments of grain or whatever other commodities (flood, earthquake, civil disorder, etc.). That's not the sort of thing that people usually mentioned in diplomatic negotiations, since the idea was to blindside the target(s).
I'm a firm believer in maps, and making sure they're accurate. It annoys me profoundly when I'm playing Fighting Fantasy when there's no way to keep a coherent map (ie. in the Star Trek ripoff they did; mapping that one was impossible). Sometimes mistakes creep into the game and aren't caught during editing or beta testing, or there might be a situation where the PC is rendered unconscious and wakes up somewhere else or gets caught and taken somewhere else and there's no way to reconcile the maps.The group was always required to keep their own map when I was the DM. I'd explain the terrain once and after that it was up to them. I always had the map so I never got confused
I once got lost in the Maze of Zagor because I wasn't careful enough with my map. I couldn't find my way out of one particular area because what I thought was a solid wall was really a smudge from the eraser on my pencil. Once I re-read that section and fixed my map, I could quit circling around back to the room where the Dwarves were playing cards (they got progressively more pissed off every time I showed up again).
Everything I've read about tabletop RPGs says that one player should be the one who does the mapping, unless the DM provides the maps (ideally only for the section(s) where the players either are, or have been). Otherwise, in the situation you describe, if they want to go back to a previous room and haven't kept a map, I'd make them do periodic rolls to see if they remember the way or if they get lost. If they take too long at it, a wandering monster encounter wouldn't be out of place.
In my novelizations of the various Fighting Fantasy books, I have my pov character make at least some attempt at a map. Actually, in Scorpion Swamp, one of the primary purposes of that quest is to make a map of the trails and clearings, and where the hazards are (as well as any friendly denizens who might live there).
