Having the bones of the past showing through the crust of the earth isn't a super complex idea. I use it a lot in many different fantasy settings. The characters in LotR are constantly travelling over, past, and through ruins and monuments to a fallen past, a past most of the characters have no clue about. Interestingly, these form the backdrop for many of the key sequences in the books. From the trolls, to Weathertop, to Rivendell, to Moria, to the breaking of the fellowship, etc the characters are often making their most important decisions literally surrounded by the past. Tolkien provides just enough pinholes via songs, legends, and exposition for the reader to catch a glimpse of this epic and fallen past. That translates pretty directly to the table top. It can also serve to make characters who are keepers of songs and lore far more interesting to play and have at the table. With the right players I'd like to let a lot of that world building fall to them, playing a game like Dungeon World for example.