“The Keep at Koralgesh is a Basic D&D game adventure for 6-8 player characters of 1st-3rd level. This dungeon is a difficult adventure for a party made up only of 1st-level characters. Since this dungeon is not intended for a party made up solely of players new to the DUNGEONS & DRAGONS game system, it is recommended that at least two or three PCs in the party should be above 1st level in experience. Note the mapping suggestions in "The Shrine of Kor" if placing this adventure in a larger campaign.”
“Adventure Background
The legend of Koralgesh is known by many, but few remember its days of glory. Prior to the adventure, the DM should familiarize the players with the following story, as it is common knowledge in the area around the Mountains of Gesh.
Note: Koralgesh was destroyed 62 years prior to the start of this adventure, but it has already faded into legend and myth in the surrounding areas. The DM should avoid giving exact dates for its destruction, but the PCs should eventually piece together the date of the Helm's Peak blast.”
I really don’t know much of anything about Mystaran geography, but unless there is something here that ties it in, it’s probably “generic world” stuff.