South Dakota Highway 25
Route of SD 25 (in red)
|Maintained by SDDOT|
|Length:||201.259 mi (323.895 km)|
|Existed:||c. 1926 – present|
|South end:||SD 50 northwest of Tabor|
|North end:||ND 18 north of Claire City|
|Counties:||Bon Homme, Hutchinson, Hanson, Miner, Kingsbury, Clark, Day, Marshall, Roberts|
South Dakota Highway 25 is a state route that runs north to south across a large portion of South Dakota. It is divided into two segments. The main segment begins at the North Dakota border, with the junction of North Dakota Highway 18 north of Claire City. Its southern terminus is at the junction of South Dakota Highway 42 south of Emery. This segment is 191 miles (307 km) long. The second segment begins at a junction with U.S. Highway 18 west of Olivet, and extends south to South Dakota Highway 50 northwest of Tabor. It is 22 miles (35 km) in length. The total length of SD 25 is just over 201 miles (323 km) in length.
When first designated in 1926, the south terminus of South Dakota 25 was at Howard. The segment from north of South Dakota Highway 262 (U.S. Highway 16 at the time) to Howard was gradually added in the 1970s as construction was completed. The segment between SD 42 and SD 262 was added around 1992.
On the north end, SD 25 in 1926 took a zig-zag route north from De Smet; it went through Clark to Webster then west about 15 miles (24 km) before heading north to Britton and the North Dakota line northeast of Kidder.
In the mid 1950s, the route was realigned so it went straight north from De Smet to U.S. Highway 212 east of Clark, then north to Webster, before resuming the previous alignment to North Dakota.
In 1976, the north portion of SD 25 was shifted east to absorb an old alignment of South Dakota Highway 23 Webster to Lake City; it then curved northeast through Veblen and north again at Hammer, on a former alignment of South Dakota Highway 15.
Also in 1976, the distinct southern segment was added, absorbing the old South Dakota Highway 35.
|Bon Homme||0.000||0.000||SD 50||Southern terminus|
|Gap in route|
|I-90 – Mitchell, Sioux Falls|
|Miner||46.658||75.089||SD 34 west||Western end of SD 34 concurrency|
|52.702||84.816||SD 34 east||Eastern end of SD 34 concurrency|
|Kingsbury||De Smet||74.594||120.047||US 14|
|Clark||88.709||142.763||SD 28||Southern end of SD 28 concurrency|
|91.699||147.575||SD 28 west||Northern end of SD 28 concurrency|
|108.755||175.024||US 212 west||Western end of US 212 concurrency|
|109.625||176.424||US 212||Eastern end of US 212 concurrency|
|Marshall||Lake City||172.054||276.894||SD 10 west||Western end of SD 10 concurrency|
|172.894||278.246||SD 10 east||Eastern end of SD 10 concurrency|
|Roberts||196.228||315.798||SD 106 south||Northern terminus of SD 106|
|Richland||201.259||323.895||ND 18 north||Continuation into North Dakota|
|1.000 mi = 1.609 km; 1.000 km = 0.621 mi