The Chicago, Burlington and Quincy introduced the three-car Zephyr in 1934 as the first in a series of lightweight stainless steel streamliners, and its initial Denver-Chicago run of 13 hours, 4 minutes brought national attention. The first four Zephyrs, including the Pioneer, Mark Twain, and the original pair of Twin Cities Zephyrs, were articulated with their power cars, while later versions used separate locomotives and, from the 1940's onward, individual non-articulated stainless steel cars. The silver Zephyr fleet became known for comfort, speed, and later amenities such as dome cars; the CB&Q built the first dome car in its Aurora Shops in 1945, and within six months forty more were ordered for the fleet. Zephyrs operated throughout the CB&Q system, with the Chicago-Oakland California Zephyr among the best known, also running west of Denver on the Western Pacific and Denver and Rio Grande Western. In articulated trains, adjacent cars share a single supporting truck and are semi-permanently coupled, a design used by the first lightweight streamliners of 1934, including the Pioneer Zephyr and Union Pacific's M-10000. Later articulated trains grew larger, sometimes up to 12 cars, but articulation declined in favor by the 1940's because repairs to one car sidelined the whole train, capacity could not be adjusted to ridership, and the entire train had to be reversed at the end of a run. The concept returned successfully fifty years later in freight cars built to carry truck trailers, cargo containers, and multi-level auto racks. In 1936, CB&Q replaced the original three-car Twin Cities Zephyrs between Chicago and Minneapolis-St. Paul with two six-car articulated trains whose cars were named for ancient goddesses on one train and gods on the other. Each set included an auxiliary power-baggage car, a diner, two coaches, a parlor-drawing room car, and a parlor-lounge-observation car; dinette-coach cars were added in 1937, and standard cars were often added at the front. In 1947, both trains were overhauled for service on the Chicago-Lincoln route as the Nebraska Zephyr; by 1964 the dinette and drawing room cars had been removed, in 1966 the dining cars became vending-machine cafeteria cars, and both trains were retired in 1968. The Train of the Goddesses was later purchased with the one remaining E5 locomotive and restored to its 1965 form as the only operational Zephyr and the only operational articulated streamliner.