The Titan's Causeway
The Titan's Causeway is an area of semi-submerged stone joining the land of the Red pillar to the large sub-continent beneath it. It is comprised primarily of weathered pink granite, typically concealed by a thick coating of corals, barnacles, oysters, sponges, and other crustaceous accretion. The top surface is generally rounded. At certain parts, it may be several hundred feet wide with tapering edges.
Due to tidal, seasonal, and geological action in the region, the Causeway barely exceeds sea level for periods of time, then recedes an average of 20 feet during others. This typically allows vessels of shallow to moderate draft to pass safely over it when it is 'down', and blocks almost all sea travel when it is 'up'. Light vessels may portage over the Causeway while it is 'up', and there are a few for-profit operations to bear larger vessels across at various point along its length. During a few exceptional seasons, it has been known to appear as high as 10 feet above sea level, or as much as 40 feet below.
Economy and Politics
Both ends of the Causeway are always above or close to sea level for several miles into the sea, making them very popular for fishermen, spear hunters, recreational swimmers, pearl cultivators, etc. Seasonal shantytowns tend to be erected as far down the exposed ends as possible while the Causeway is submerged. When it emerges, it is frequented by street vendors or bazaars catering to travelers. These are most commonly Ifrit, Shard, and Grey Orc. The political and economical stability of the causeway has come into question many times, though it has never actually come under dispute or been the catalyst for aggression or disagreement. The seasonal shantytowns sometimes breed crime if the Causeway is 'Down' for an extended period, but that usually abates naturally as vendors and travelers begin to frequent it again during 'up' times.