Reconstruction of the Karakoram Highway the China-Pakistan Friendship Tunnels can be traced to 2013, when China began construction on a bypass of Attabad Lake with a combination of 5 km worth of tunnels, two large bridges, and 78 small bridges to bypass the lake which had been formed after a 2010 earthquake triggered massive landslides. The resulting landslides cut off both the Indus River and Karakoram Highway resulting in the formation of the reservoir. Prior to completion of the bypass, all vehicular traffic had to be loaded onto barges to traverse the new reservoir. Construction of the tunnels began in 2012 and required 36 months
Puerto Rico Highway 1 of what became PR-1 began with the building of the "Carretera Central", started during the governorship of Miguel de la Torre (1822-1837). A small section from San Juan to Río Piedras was then started. The Carretera Central proceeds south to Cayey along the route of the PR-1, then diverges, and was completed in 1887, taking over 50 years to complete. The Road was also known as "La Carretera Militar" (The Military Road). The modern PR-1 was opened on 10 March 1907. Puerto Rico Highway 1 Puerto Rico Highway 1 (or PR-1) connects the city of Ponce to San Juan. Leaving