Way back in college I also played The Fantasy Trip. Steve Jackson Games had a Kickstarter and raised quite a bit to bring it back now that he has the rights again. I went overboard (darn KS addiction) and got the I Want It All (and then added more...)
So I also dug up my old college maps - I actually made an atlas based on all the miniatures I had bought over the years (and why I thought having ALL the skeletons was a good idea I cannot recall). I built this atlas with hand-drawn maps (I really loved colored pencils apparently) and taped them together into a book of about 10 maps or so. Each region was specific to a race primarily, with a bit of overlap.
Another recent Kickstarter is a "drop-in" resource. The Woodfall Kickstarter presents a witch town in a fen, along with inhabitants, surrounding region, and a lot of fun things. So I found a place to plug it in, next to the Terror Lands which is a giant marsh.
My plan is next year to run a fantasy game using those rules, and using the old maps and things. I do have a major city that the adventurers will start in, and I also have the Complete Ankh-Morpork City Guide, which came with a HUGE map (and was on sale for $5. The map alone is worth that). So my city has an unerring similarity to Ankh-Morpork as well.
As mentioned in a previous post on Pax Stellar being based on another art book - I am finally, after almost 40 years, figuring out how to integrate all the stuff I've accumulated over the years into something I hope will be fun for other people.
So, End City is on a river, so that works for me as well. And I've rumors about Stuboon's lost treasure (I even have a history of the world and its own gods. At the time I was a college student, could not afford what I could find, so making it up was both entertaining and cheap. Stuboon thought a shortcut would give him a marketing edge from the north lands to End City. As witness the 3 stands, it did not work out well after all).