The Undershores

Urth has a number of coastlines that are ragged drops into the sea. The land may end abruptly in a thousand-foot or more drop, sometimes for hundreds of miles. This can result in massive cave systems running under the shoreline. Commonly called Undershores, the sea can actually run into them. Some of the highest ceilings are known to be 600 feet high. When a deep enough channel is available, ports have been built under the land. The undershores can run for miles underground. Not surprisingly some connect to the deeper underdark. With softer rock washed away, the walls and pillars are often solid granite or other dense stone. Buildings can be carved into the sides. Sinkholes in the land above are common, some will drop fully to the sea level. Others hit shelves where fresh waters pool before winding lower. In the undershore, freshwater comes from above not below.
There are many settlements within the undershores. Ancient homes have been found carved into the rocks. And they show signs of being reused and altered time and again across hundreds or thousands of years. Typically the names of these towns denote their position, incorporating low, down, under, 'neath or other terms into the town name. If there is no easy access to grounds above with fertile fields for farms, they tend to be heavily trade-oriented and craft towns. These rely on foods brought in by nearby villages through caravans or ships. But they encourage sink holes and cenotes, so paths to the surface are common. Several large shoreline cities develop both with infrastructure bridging the two into one city. Crystfallen in West Krahnis is a massive city on its own, but there are four miles of undershore serving as her port and some of the proverbial seedy underbelly.
The shelter and hidden nature of these cavern systems make them often used by unsavory denizens. Pirates, illegal traders, and refugees find shelter there. Living in a cave, even ones with 200-foot -high openings to the outside is not for everyone. Some inhabitants are quite poor and destitute, but they welcome free homes safe from harsh weather.

Type

Cave System