State Route 73 (SR 73) is an approximately state highway in Orange County, California. The southernmost of the highway is a toll road operated by the San Joaquin Hills Transportation Corridor Agency named the San Joaquin Hills Transportation Corridor, which opened in November 1996. The northernmost of the highway, which opened in 1978, is part of the Corona del Mar Freeway. SR 73's southern terminus is at Interstate 5 (I-5) in San Juan Capistrano and its northern terminus is at Interstate 405 (I-405) in Costa Mesa. The highway's alignment through the San Joaquin Hills follows an approximately parallel path between the Pacific Coast Highway and I-405. Currently, there are no HOV lanes for the three-mile freeway segment, but the medians have been designed with sufficient clearance for their construction should the need arise in the future. Route description SR 73 begins in northern San Juan Capistrano near the Mission Viejo border at an interchange with I-5. The freeway heads northwest into Laguna Niguel before the tolled portion begins at the Greenfield Drive exit. After passing Greenfield Drive, SR 73 enters Aliso Viejo before entering Laguna Beach, where SR 73 has an interchange with SR 133. Following this, the road passes through Crystal Cove State Park, where the main toll plazas are located. After leaving the state park, SR 73 straddles the border between Irvine and Newport Beach and provides easy access to University of California, Irvine through the Bison Avenue exit. Following the MacArthur Boulevard exit, the tolled part of the road ends and becomes a freeway. SR 73 continues into Newport Beach, running along the southern boundary of Orange County John Wayne Airport (IATA Airport Code SNA). Entering Costa Mesa, SR 73 interchanges with SR 55 before ending at I-405. SR 73 is part of the California Freeway and Expressway System, and is part of the National Highway System, a network of highways that are considered essential to the country's economy, defense, and mobility by the Federal Highway Administration. History Most of SR 73 is a limited-access toll highway designed to reduce congestion within Orange County on the Pacific Coast Highway (SR 1) and the San Diego Freeway (I-5 and I-405) by providing a direct route through the San Joaquin Hills. SR 73 is not a toll road over its entire length. From its northbound terminus heading southbound, the first of SR 73 has no tolls and is known