Route history

The road to Fredericksburg became SH 9 as part of the first state highway system designated in 1917. By the early 1920s, it also became part of SH 27 to Kerrville.

This road was also part of the Old Spanish Trail, a transcontinental auto trail with its headquarters in San Antonio. The section of road between San Antonio and Boerne was known as the "Headquarters Section" and was used to test various road improvements such as pavements, alignments, and safety features and became a model that other localities could emulate.

When the US Highway System was first designated in 1925, this road was numbered US 290, which ran via Comfort to Kerrville and points west. Meanwhile, the road from Comfort to Fredericksburg (SH 9) was numbered US 385. Initially, these routes met in Comfort, but by the late '20s, it appears the route for US 385 was rerouted away from Comfort and instead ran through Waring and Welfare to meet US 290 at Nelson City (where PoPo's is), likely to facilitate a more direct route to San Antonio. Although the official southern terminus for US 385 was listed as being at its junction with US 290, it appears that by 1932, US 385 was co-signed with US 290 along the Fredericksburg Road into San Antonio, likely to provide a more logical terminus for the route in San Antonio.

In a 1935 revision of the system, US 87 was extended south from Wyoming into Texas and supplanted US 385. At the same time, US 290 was rerouted east from north of Mountain Home through Fredericksburg, Austin, and on to Houston, leaving the segment from Comfort through Kerrville and Mountain Home as SH 27. Finally, a new road for US 87 from Fredericksburg to Comfort was also completed around that time.

In Bexar County, the route has been fairly stable, running along Fredericksburg Road in San Antonio. Around today's Loop 1604, the route initially used what's now Old Fredericksburg Road; this was bypassed by the current route in the mid '30s.

In Leon Springs,the first road ran parallel to and just to the east of the main road through Leon Springs today (i.e. that little road behind Rudy's.) Prior to the state highway system, one route from Leon Springs to Boerne continued along what's now Old Fredericksburg Road northward. However, it appears the initial state highway turned left onto Boerne Stage Rd. and followed it northwest and then curved north onto Scenic Loop Rd. and continued into Kendall County. The route entered Boerne on Old San Antonio Rd. and curved left onto Oak Park Dr. and right onto Main St. through Boerne. North of Boerne, the route crossed back and forth on today's I-10 right-of-way to Nelson City. There, the route curved onto today's FM 289 and onto the Waring-Welfare Rd. to the T intersection at Green Cedar Rd. There, SH 9 turned right to Welfare while SH 27 turned left and continued mostly on today's FM 289, Old Comfort Road, and High Street Rd., before crossing the Guadalupe River on the High St. bridge into Comfort.

By the mid '30s, the route through Leon Springs shifted a couple hundred feet west (today's main road through Leon Springs) where it continued north-northwest on a new road (today's path for I-10) that had been built between Leon Springs and Boerne to replace the route along Scenic Loop Road. Further north, several sections of the route between Nelson City and Comfort were straightened and a new bridge over the Guadalupe River (today's Business US 87) was built.

San Antonio's first expressway was built to provide a bypass for US 87 from Fredericksburg Rd. at Woodlawn into downtown. US 87 from Woodlawn to Huebner was shifted from Fredericksburg Rd. to I-10 after it was completed in the mid '60s. Fredericksburg Road west of I-10 was then redesignated SL 345 but was signed as Business US 87 until the early '90s.