Texas State Highway 123

State Highway 123
Route information
Maintained by TxDOT
Length	69.1 mi (111.2 km)
Existed	by 1933–present
Major junctions
South end	US 181 / Bus. US 181 / SH 80 in Karnes City
North end	I-35 / Loop 82 in San Marcos
Location
Country	United States
State	Texas
Highway system
Highways in Texas Interstate US State Toll Loops Spurs FM/RM Park Rec
← SH 122 → SH 124

State Highway 123 is a north–south state highway that extends from Interstate 35 in San Marcos to US 181 in Karnes City. The route was initially proposed in 1927 and has had minimal changes to its routing since then.

Route description

SH 123 begins at an intersection with US Route 181 just south of Karnes City and proceeds northward along the town's eastern edge. The route intersects the Business Route of US 181 and Texas State Highway 80 as it passes through town. The road continues north through farmlands before reaching an intersection with US Route 87 in Stockdale. The route continues north through ranchlands until Seguin. Reaching Seguin, Texas State Highway 46 begins, peeling off to the northwest toward New Braunfels. SH 123 continues around the eastern edge of Seguin, where it is known locally as "the Bypass", and there it intersects US 90 Alt., US 90, and Interstate 10. The highway continues north, reaching its northern terminus at Interstate 35 in San Marcos.

The route has two business segments: Business 123-B, largely on Austin St, through historic downtown Seguin, and Business 123-D in Karnes City.

Route history

The route was initially proposed on April 12, 1927 from Stockdale to San Marcos with a proposed extension south to Karnes City. On September 21, 1931, it was rerouted to end in Floresville. On August 4, 1932, it was restored to Karnes City, and the old route was renumbered as SH 168. On November 6, 1934, it was rerouted to Yorktown. On February 16, 1935, its south end was changed back to Karnes City. On November 18, 1938, SH 123 Loop was designated in Karnes City. On September 26, 1939, SH 123 Loop was renumbered as Loop 17. Paving was completed in the mid-1940s.

Major intersections

County	Location	mi	km	Destinations	Notes
Karnes	​			US 181 – Kenedy, Corpus Christi, San Antonio	south end of US 181 Bus. / SH 80 overlap
	Karnes City			Bus. US 181 north	north end of US 181 Bus. overlap
				SH 80 north – Helena, Gillett	north end of SH 80 overlap
	​			Bus. SH 123 south – Karnes City
	​			FM 81 east – Panna Maria	south end of FM 81 overlap
	​			FM 81 west – Hobson	north end of FM 81 overlap
	Pawelekville			FM 887 – Falls City, Gillett
Wilson	​			FM 541 west – Kosciusko, Poth
	​			FM 1347 – Kosciusko, Denhawken
	​			FM 537 west – Floresville
	Stockdale			US 87 / SH 97 to SH 119 – Floresville, San Antonio, Nixon	interchange
				Bus. US 87 (Main Street) – Stockdale Business District, Pandora, Nixon
	​			FM 3335 east to FM 1107
	​			FM 1681 east – Nixon
Guadalupe	​			FM 477 east
	Seguin			SH 46 north / Bus. SH 123 north – Seguin, New Braunfels
				FM 466 (Eastwood Drive) to SH 80 – Seguin
				US 90 Alt. (Court Street) – Seguin, Gonzales, Texas Lutheran University, Sebastopol Historical Park
				US 90 – Seguin, Luling
				I-10 – San Antonio, Houston	I-10 exit 610
				Bus. SH 123 south – Seguin
				FM 20 east – Fentress
	Geronimo			FM 2623 east – Fentress
	​			FM 758 west – Barbarosa, New Braunfels Municipal Airport, Central Texas Technology Center
	​			FM 1339 east – Staples
	​			FM 1101 west – New Braunfels
	Zorn			FM 1979 east – Martindale
	​			FM 1978 east – Redwood
Hays	San Marcos			FM 110 west
				RM 12 north (Wonderworld Drive)
				FM 621 east – Staples State Fish Hatchery
				I-35 / Loop 82 – San Antonio, Austin
1.000 mi = 1.609 km; 1.000 km = 0.621 mi