is twice the route mileage. The remainder, 5,274 miles, consists of two-way streets.
Urban surface widths
Of the street mileage of one-way streets, a total of 1,390 miles, only 168 miles are as much as 40 feet wide; 366 miles are between 30 and 40 feet wide; the largest fraction, 835 miles, are between 20 and 30 feet wide; and 21 miles are less than 20 feet in width.
Of the two-way streets, 2,069 miles are less than 30 feet wide, 1,011 miles are between 30 and 40 feet wide; 1,747 miles are between 40 and 60; and 447 miles are more than 60 feet wide.
Rural surface widths
Of the 31,831 miles of the system in rural areas, 31,816 miles are surfaced, and of this mileage 27,669 miles have two-lane surfaces. There are 241 miles on which the two-lane surface is less than 18 feet wide, and an additional 5,868 miles on which it is between 18 and 20 feet wide. More than 40 percent of the existing two-lane surfaces, 11,637 miles, are between 20 and 22 feet wide; 4,694 miles are between 22 and 24 feet; and only 5,229 miles are as much as 24 feet in width.
Of the rural mileage surfaced with more than two lanes—a total of 4,147 miles—1,607 miles have three lanes; 1,056 miles have four or more lanes without central division; and 1,484 miles are improved with pavements centrally divided for separation of traffic of opposite direction. Nearly 11 miles of these divided pavements have six or more lanes; 1,473 miles have four lanes, two for each direction of traffic.
