Utah State Route 170 (pre-1969)

A number of minor state highways in the U.S. state of Utah were deleted by the State Legislature in 1969.

State Route 50 was originally a branch of SR-122, but was split off as its own route in 1935, running from Wattis southeast to SR-122 east of Hiawatha. This route was deleted in 1969, with the route number immediately reused for the road between Roy and Ogden (Riverdale Road), which was subsequently renumbered to SR-26 as part of the 1977 Utah state route renumbering in order to avoid confusion with US-50.

State Route 53 connected SR-8 (now US-6/US-191) at Wellington with SR-6 (now US-40) west of Myton via Nine Mile Canyon Road. The road was taken over on January 10, 1916, and immediately reused to replace part of SR-37 in Ogden after its 1969 deletion.

State Route 55 connected Cedar Breaks Junction on SR-14 to the south boundary of Cedar Breaks National Monument, a distance of about 2.5 miles (4.0 km). This route was designated on June 17, 1927 as part of SR-14, and split in 1931. It was withdrawn as a state route in 1969 and re-designated as part of SR-143. Later, in 1985, this route was split off from SR-143 and designated as a distinct highway, SR-148, while SR-143 was extended to run along the rest of Panguitch Lake Road, north and east of Cedar Breaks until US-89 in Panguitch. SR-148 now follows the same route of former SR-55. The SR-55 route number was reused in 1975 as a business loop for US-6 in Price.

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