Giant's Causeway cases the horizontal fracture has resulted in a bottom face that is convex while the upper face of the lower segment is concave, producing what are called "ball and socket" joints. The size of the columns is primarily determined by the speed at which lava from a volcanic eruption cools. The extensive fracture network produced the distinctive columns seen today. The basalts were originally part of a great volcanic plateau called the Thulean Plateau which formed during the Paleocene. According to legend, the columns are the remains of a causeway built by a giant. The story goes that the Irish
Cave-In-Rock, Illinois Logan Belt Gang terrorized Hardin County in the 1870s and 1880s, until Belt was assassinated. In the middle of the 1800s, church services were being held in the cave. This earliest Christian congregation eventually formed the Big Creek Baptist Church. Founded in 1807, it was the first church organized in southeastern Illinois. Cave-In-Rock incorporated in 1839, in the same year that Hardin County was created from a section of Pope County. According to the Illinois Department of Natural Resources, "in 1929, the State of Illinois acquired for a park that since has increased to . The well-wooded, hills and the