The Ancient Signal Towers were the first navigational tool used on The Ancient World.
Pre-dating the use of maps and compasses, they were used day and night as a point of reference for the surrounding area. The towers were always built within view distance to each other so that Mortal explorers were able to navigate their way from one to the next, using them as landmarks.
Some of the towers feature modest living quarters for Mortals to rest and recuperate safely. The towers are built entirely of cobblestone mined from The Deadly Mines.