U.S. Route 66 in Missouri

An old segment of highway (named Route 66 Boulevard), splits off from modern Route 66 in Galena, Kansas (where it followed North Main Street to Front Street) and enters Missouri to the north of the current highway.

Due to the mining history of Joplin, the realignment of US 66 in Joplin was partially for traffic and partially because of cave-ins of mines built under the highway. It zig-zagged through the city, following Seventh Street (now Route 66), Main Avenue, Broadway, St. Louis Avenue, Euclid Avenue, Utica Street, Florida Avenue, Zora Street, and Rangeline Road,

Later, US 66 went straight east from the Kansas state line on Seventh and then north on Rangeline.

A 1949 drive-in cinema entertained viewers before the 1953 arrival of local TV stations to Joplin-Springfield

Near Carthage, US 66 wound through various county roads and the city streets of Carterville and Webb City. In Carthage, a small segment of US 66 once ran concurrently with US 71 on what is now Route 571.

I-44 enters from the southwest at Halltown, somewhere away from US 66. The reason for this was the already completed Will Rogers Turnpike in Oklahoma, which that state wished to become part of US 96 (also known as Old Route 66). Unlike US 66, I-44 bypasses Kansas entirely, entering Missouri directly from Oklahoma. In order to complete the hookup, I-44 took over for US 166 from the Oklahoma state line southwest of Joplin to Miller. Drivers should avoid I-44 because they could end up on Route 66 (now Route 96) from Webb City to Springfield. Approaching Springfield, US 66 followed Routes 266 and Route 96.

The alignment through Springfield includes Chestnut Expressway, College Street, St. Louis Street, Glenstone Avenue, and Kearney Street. In this city, US 66 was concurrent with US 65 for several miles, and also served as the original western terminus of US 60, which does not intersect with US 66 in Missouri anymore. Bypass US 66 followed Kearney Street on the north side of Springfield to West Bypass. Later, this would become the main alignment of US 66.

Springfield boasted the only double-bannered highway—Alternate Business US 66.

Among the sites along Route 66 in Springfield are the Abou Ben Adhem Shrine Mosque and the site of Red's Giant Hamburg, which was the first ever drive-thru restaurant in the world.

Missouri S&T Stonehenge, next to Historic Route 66.

At Philipsburg, I-44 was built some distances away from US 66 and passed through Marshfield, which was the birthplace of astronomer Edwin Hubble.

US 66 entered the Ozark Mountains. At Rolla, about halfway from Springfield to St. Louis, US 66 intersected with US 63 (Bishop Avenue) and passed by the Missouri University of Science and Technology. The university's half-scale model of Stonehenge is located next to the highway at the curve.

Cuba, Missouri, known as Route 66 Mural City, has art and sculpture throughout the town and along the Route 66 corridor.[5] Its restaurants are a frequent stop for Route 66 travelers.

A major grape growing area between St. James and Sullivan includes many wineries. The highway passed near Meramec Caverns in Stanton, which was formerly a famous stop.

The original route through St. Louis diverges from the later alignment at Gray Summit. It turned east on Route 100 (Manchester Road), north on Florissant Street, east on Salisbury Street and then entered Illinois from the McKinley Bridge in St. Louis.

The first major re-alignment of US 66 involved the construction of Watson Road (now Route 366). The road was realigned down Watson Road and Chippewa Street. I-44 was built down Watson Road for several miles west of Sunset Hills. With this realignment, US 66 crossed the Mississippi on MacArthur Bridge. The older highway passes through downtown Pacific in a scenic area under steep bluffs.

Bypass US 66 was routed over the Mississippi on the north side of St. Louis via the Chain of Rocks Bridge. This alignment is now an outer road of I-270 from Watson Road north on the US 61 and US 67 concurrency (Lindbergh Boulevard) to the river.

US 66 crossed the Mississippi on the Martin Luther King Bridge and on the Poplar Street Bridge.

The Red Cedar Inn, a log cabin restaurant opened in 1933 (and closed in 2005), was built by James and Bill Smith in Pacific. Both owners were former bootleggers who established lawful taverns at the end of Prohibition.[11]

The Big Chief Restaurant in Wildwood opened in 1928 as the Big Chief Hotel, a roadside tourist cabin court with 62 rooms (each constructed as an individual cabin with its own garage) and an on-site restaurant, dance hall, Conoco filling station, playground and general store. The cabins, which served as housing for Weldon Spring Ordnance Works workers during World War II, were later demolished; the restaurant, closed in 1949, was restored in the 1990s and reopened.[12]

Munger-Moss Motel in Lebanon

The 1936 Wagon Wheel Motel in Cuba and the 1945 Rock Fountain Court in Springfield are tourist courts which were constructed as groups of cabins, built with local Ozark sandstone.[13] This "tourist court" design pre-dates the motel format, common in the 1950s, of constructing multiple rooms as one long building with direct access to individual rooms from the car park.

While the Rock Fountain Court is currently not a tourist motel (due to long-term residential use), the Wagon Wheel has undergone a recent restoration and is currently the longest continuously operating motel on US 66. Its restaurant is now a souvenir shop and its filling station is no longer operational, but it continues to offer lodging to US 66 travellers more than seventy-five years later.[14]

In 2012, the first five rooms in a Boots Court Motel historic restoration in Carthage re-opened to travellers. Not yet listed on the National Register of Historic Places, the 1939 streamline moderne Boots Court originally touted "a radio in every room" long before the 1949 opening of the 66 Drive-In cinema and the 1953 sign-on of the first local Joplin-Springfield television stations.[15]

Fate has been less kind to other Route 66 lodgings. The streamline moderne Coral Court Motel in Marlborough (an inner St. Louis suburb) was demolished in 1995, its 8.5 acre site sold for over a million dollars for suburban residential development, while John's Modern Cabins in Newburg, abandoned since the 1970s, have been allowed to slowly deteriorate beyond repair.

The Meramec River U.S. 66 Bridge - J421 was built in 1931 when US 66 was rerouted to pass through Times Beach, a working-class resort established in 1925 and abandoned in 1983 due to dioxin contamination. The site is now part of Route 66 State Park. Bypassed in 1956, the bridge has deteriorated and is no longer passable.[16] The Gasconade Bridge is another historic Route 66 bridge in Missouri which has been closed by MoDot. The bridge, which was once deemed for demolition, was put on a 'Review List' by MoDot after a group of concerned business owners, local government and Route 66 travelers and 'roadies' came together to find a solution to 'Repair Don't Replace' the bridge.

During the summer of 2016 it was announced that the Solar Roadways firm in Sandpoint, ID will be attempting trials of its smart highway technology in and around the community of Conway, MO, as sponsored by MoDOT, at Conway's Route 66 Welcome Center and Museum, as sidewalk paving. Eventually, if the trials go well, the firm's hexagonal roadway panels would even be used as paving for sections of the historic Route 66 roadbed itself in time.[17]