| State: | KS |
| Type: | K 1962 |
| Route: | 129 |
| Map Custom: | yes |
| Map Notes: | Former K-129 highlighted in red |
| Length Mi: | 3.25 |
| Established: | October 22, 1947[1] |
| Decommissioned: | 1966 |
| Direction A: | South |
| Direction B: | North |
| Terminus A: | in Beloit |
| Terminus B: | in Beloit |
| Counties: | Mitchell |
| Previous Type: | KS |
| Previous Route: | 128 |
| Next Type: | KS |
| Next Route: | 129 |
| Next Dab: | 1980–1997 |
K-129 was a 3.25adj=midNaNadj=mid state highway in the U.S. state of Kansas. K-129's southern terminus was at U.S. Route 24 (US-24) in the city of Beloit and the northern terminus was at US-24 and K-9 in Beloit. Within the city, the highway briefly overlapped K-14.
K-129 was first designated as a state highway on October 22, 1947, to a highway running from the north city limits of Beloit to K-9. On February 28, 1951, it was approved to realign US-24 further along K-9 and to the east of Beloit. Around this time K-129 was extended south to K-14, then along the former routing of US-24.
K-129 began at US-24 southeast of Beloit and began travelling west along Asherville Road. The highway then curved north becoming Brooklyn Avenue until reaching Elliot Street where it turned back west. It then intersected River Street, where it turned north and crossed a series of railroad tracks. After crossing the tracks, K-129 turned west onto East South Street then intersected K-14. At this point K-129 turned north and began to overlap K-14. The two routes continued north for 0.13miles and intersected at the western terminus of K-124 (East Main Street). K-129 and K-14 continued north for another 0.5miles before reaching East 8th Street, where K-14 turned west and K-129 continued north along North Hershey Avenue. It continued north for then curved east briefly before turning back north onto North Walnut Street. K-129 continued past the then reached its northern terminus at US-24 and K-9.[2]
K-129 was first designated as a state highway on October 22, 1947, and at that time ran from K-9 south to the north city limits of Beloit.[1] The section of K-129 from its southern terminus to the north end of the K-14 overlap was originally part of US-24. US-24 was approved to be realigned to the east of Beloit in a February 28, 1951 resolution.[3] Around this time K-129 was extended south to K-14, then along the former routing of US-24.[2]