The Cumberland Gap is a pass in the eastern United States through the long ridge of the Cumberland Mountains, within the Appalachian Mountains and near the tripoint of Kentucky, Virginia, and Tennessee. At an elevation of above sea level, it is famous in American colonial history for its role as a key passageway through the lower central Appalachians. Long used by Native American nations, the Cumberland Gap was brought to the attention of settlers in 1750 by Thomas Walker, a Virginia physician and explorer. The path was used by a team of frontiersmen led by Daniel Boone, making it accessible to pioneers who used it to journey into the western frontiers of Kentucky and Tennessee. An important part of the Wilderness Road, it is now part of the Cumberland Gap National Historical Park. Geography The Cumberland Gap is one of many passes in the Appalachian Mountains, but the only one in the continuous Cumberland Mountain ridgeline. It lies within Cumberland Gap National Historical Park and is located on the border of present-day Kentucky and Virginia, approximately northeast of the tri-state marker with Tennessee. The V-shaped gap serves as a gateway to the west. The base of the gap is about above the valley floor, even though the north side of the pass was lowered during the construction of Old U.S. Route 25E. To the south, the ridge rises above the pass, while to the north the Pinnacle Overlook towers above at an elevation of . Centrally located in the eastern United States, the region around Cumberland Gap experiences all four seasons. The summers are typically sunny, warm, and humid with average high temperatures in the mid to upper 80s °F (29-32 °C). In the winter months, January through March, temperatures range in the 30s to 40s °F (0s °C) and are generally mild with rain and few periods of snow. The nearest cities are Middleboro, Kentucky, and Harrogate, Tennessee. The nearby town of Cumberland Gap in Tennessee is named after the gap. Geology The gap was formed by the development of three major structural features: the Pine Mountain Thrust Sheet, the Middlesboro Syncline, and the Rocky Face Fault. Lateral compressive forces of sedimentary rocks from deep layers of the Earth's crust pushing upward 320 to 200 million years ago created the thrust sheet. Resistance on the fault from the opposing Cumberland Mountain to Pine Mountain caused the U-shaped structure of