intersection, Niagara Regional Road 63 (Port Robinson Road). North of Port Robinson Road, the forests break and the freeway continues straight north for through a mostly agricultural area. Along the straightaway are interchanges with former Highway 20 and Niagara Regional Road 67 (Beaverdams Road). The freeway crosses over Lake Gibson, and curves to the northeast. It passes beneath Niagara Regional Road 71 (St. Davids Road) and Highway 58 at a complicated interchange as it descends the Niagara Escarpment, a UNESCO Biosphere Reserve, and enters St. Catharines. Within St. Catharines, Highway 406 twists frequently, entering the Twelve Mile Creek valley south of a complicated interchange with Westchester Avenue and Geneva Street and curving west. Within the valley, the freeway features a lower design speed and reduced speed limit of . It passes beneath the high-level St. Paul Street bridge, crosses the creek and intersects Fourth Avenue. Exiting the creek valley, the freeway parallels Fourth Avenue for a , gradually curves to the north and ends to the north, ending at a trumpet interchange with the QEW. History Planning for Highway 406 began in early 1959, when Minister of Highways Fred M. Cass presented the Ontario Roads and Streets report to the Ontario Legislative Assembly on March 16, outlining highways needs for the province over 20 years. One of the planned routes was a freeway to link Highway 3 in Port Colborne with the QEW, travelling alongside the Welland Canal. By 1961, route studies and planning were well underway. The future route was designated as Highway 406 despite construction not beginning until 1963; the first section, between Geneva Street and St. Davids Road, opened December 7, 1965. This was followed several years later by an extension south to Beaverdams Road, which opened November 21, 1969. During the early 1970s, the highway was extended south as a Super 2 to north of the Welland River, where it curved west along Merritt Road and became Highway 58. This extension, which included the Beaverdams Road interchange and a signalized intersection, was opened on June 30, 1971. In 1977, construction began on the section of Highway 406 between Geneva Street and the QEW. This work included the construction of several large bridges over the widened ravine, a curving structure over Twelve Mile Creek, and the first single-point urban interchange (SPUI) in Ontario (the only other SPUI is located on Airport Parkway in Ottawa). The original design