Treasure maps were listed on the random treasure tables in early D&D editions, from OD&D through all 3 basic sets, and AD&D 1e and 2e. In OD&D 1/4 of magic items would be maps instead, leading to new adventures. (Kenneth Rahman, from "Minarian Legends: The Bilge Rat and the mercenary fleets of Minaria" by Glenn Rahman, Dragon 48, April 1981)










