TN 29 Valdeau to Rockwood 1924 Official

TN 31 Kingston north to Kentucky 1924 Official

TN 31 renumbered as part of TN 29 1929 Official

Also in 1928, US 27 was added to the entirety of TN 29.
Also in 1928, TN 29 was removed from Old Dayton Pike in Red Bank; Old Dayton Pike at the TN 153 jct area; Springfield Rd (no longer crosses Chickamauga Cr) and Walden St in Soddy Daisy
Also in 1928, TN 29 was removed from Liberty Rd to Liberty and TN 62 west to Wartburg; if TN 29 used Kingston St/Old Gobey Rd/abandoned routing back across modern US 27 to old US 27 at Montgomery Rd near Wartburg, it stopped doing so in 1928.
In 1931 or 1932, TN 29 was removed from today's Old TN 302/TN 302 into Graysville and Old Graysville Rd to Dayton. It is uncertain how TN 29 ran through Dayton then but best guess is Illinois/California/Delaware to TN 378.
Also in 1931 or 1932, TN 29 was removed from Cemetery Rd/McGoffin Ave/Front St through Spring City; Edwards Ln north of Piney River bridge; all of the now-discontinuous Dixie Lee Hwy segments around Roddy.
It is unclear when TN 29 was removed from Old Dayton Pike/Depot St in Soddy Daisy but I believe it was by 1932.

TN 29 alignments - notice the multiple RR crossings 1930 Official

TN 29 on more direct alignment 1932 Official

By 1935, TN 29 was removed from Springfield Rd (no longer crosses Chickamauga Cr) in Soddy Daisy; Coulterville Pike through Coulterville; Old Dayton Pike at the Rhea-Hamilton Line; Old Evensville Rd in Evensville
In 1947, TN 29 was removed from Old Dayton Pike south of Bakewell and Old Dayton Rd north of Bakewell
In 1953, TN 29 was removed from Kingston Ave/Molyneux St/Kingston Ave through Rockwood; Old kingston Hwy and Old Hwy 70/Post Oak Valley Rd esat of Rockwood; Headwaters Dr/Poland Hollow Rd at the Caney Creek Marina area; Old Hwy 70/Ruritan Rd west of Kingston
In 1957, TN 29 was removed from Pansy Hill Rd in S Harriman; Emory Dr/Sewanee St/Morgan Ave in Harriman
In 1959, TN 29 was removed from Sand Cut Rd out of Oneida; Tipple Rd; Poplar Ln; N. Old Hwy 27 in Winfield
In 1963 or 1964, TN 29 was rerouted at Harriman to follow TN 61 north 4 miles, then northwest as new primary routing to meet the old TN 29 routing. The route from Harriman via the Oakdale area became TN 29A (now TN 328).
Between 1952-73, TN 29 was removed from Tunnel Hill Rd to Old US Hwy 27 through Mountain View; Sycamore Ln (no longer crosses New River)
In 1975, TN 29 was removed from Old US 27 stubs at the railroad crossing south of Sunbright and a small bit of Cumberland Mountain Cir nearby
About 1977, TN 29 was moved from Dayton Blvd onto the new freeway between TN 153 and TN 319, with TN 29 using today's TN 319 between the old and new routing.
Also in 1977, TN 29 was removed from Main St through Wartburg and Old Hwy 27 north out of Wartburg
In 1983, TN 29 south was extended with US 127 north to the longtime freeway south across the Tennessee river to connect to I-124. This freeway had been TN 27 Spur up to that time.

TN 27 Spur connects to I-124 1964 Official

TN 29 replaces TN 27 Spur 1989 Official

Also in 1983, TN 29 was placed on the Dayton Bypass, replacing TN 29 Byp. The old route through town became TN 378. County maps showed TN 29A through Dayton, so TN 29 may have been removed from Dayton in 1961.
About 1984, TN 29 was moved from Dayton Pike onto new freeway north of today's TN 319 in Soddy Daisy.
In 1988, TN 29 was moved from Dayton Blvd plus a little US 127 plus the north end of TN 153 to the new freeway bypassing Red Bank.

TN 29 new freeway around Soddy Daisy 1986 Official

TN 29 new freeway around Red Bank 1993 Official

In 1990, TN 29 was removed from Sycamore Ln (no longer crosses New River) south of Huntsville; also abandoned routing and Glass House Rd/Memorial Dr through Huntsville
In 1996, TN 29 was removed from Woods Hill Rd, Galloway Dr and Underpass Dr south of Oneida
In 2003, TN 29 was removed from Medlin Pike through Evensville; Pennine Rd/Old SR 29 pieces in Pennine: Roddy Straight Ln at Roddy
In 2004, TN 29 was removed from Foust Hwy between Midtown and S. Harriman and instead stayed with US 70 east further to then head through the I-40 interchange as it does today.

TN 29 via the Oakdale area 1940 Official

TN 29 rerouted via TN 61 1971 Official

TN 29 rerouted to intersect I-40 2004 Official

Posting: TN 29 is posted only between US 70 near Kingston and US 27 Harriman, as a secondary route; TN 29 is considered primary routing everywhere it is paired with US 27
Secret US Route Overlay: US 27 I (69.9 mi)
US 27 II (62.0 mi)
Comment: It's a little odd that TN 29 did not follow US 27's move to the direct Rockwood-Harriman routing
TN 29 is a good alternative to I-75 from Chattanooga to I-40