Geology of Ireland Geology of Ireland The geology of Ireland consists of the study of the rock formations in Ireland. The island contains rocks from every age from Proterozoic to Holocene and a large variety of different rock types is represented. The basalt columns of the Giant's Causeway together with geologically significant sections of the adjacent coast have been declared a World Heritage Site. The geological detail follows the major events in Ireland's past based on the geological timescale. The oldest known Irish rock is about 1.7 billion years old and is found on Inishtrahull Island off the north coast of Ulster. Outcrops
S bridge part of the original National Road, which was built circa 1825. The S Bridge in Berks County, Pennsylvania, and the Claysville S Bridge in Washington County, Pennsylvania, are listed on the National Register of Historic Places. Another S bridge, in Anderson County, Kentucky, is located on U.S. Route 62 east of Lawrenceburg. It has undergone major roadway replacement and has been widened. Another S bridge of note is located in Hertford, North Carolina. It connects a causeway from Winfall to the Town of Hertford, over the Perquimans River. S bridge An S bridge is a bridge whose alignment follows a