Hays County Texas map

Hays sits between the two largest cities of Central Texas and belongs to the Austin metropolitan statistical area. Austin is 22 miles northeast, New Braunfels 25 miles south, Round Rock 37 miles northeast and San Antonio 52 miles southwest. San Marcos, on I-35 near the county's southern end, is almost exactly halfway between Austin and San Antonio.

The Balcones Escarpment cuts across the county from southwest to northeast, more or less along the line of I-35. Most of Hays County lies west of it on the Edwards Plateau — hills, spring-fed creeks and thin soil over limestone — while the southeastern corner drops onto the Blackland Prairie. Two rivers cross it: the Blanco, which enters from Blanco County and joins the San Marcos below the city, and the San Marcos itself.

Five counties border it: Travis to the northeast, Caldwell east, Guadalupe south, Comal southwest and Blanco northwest.

The county was created out of Travis County in 1848 and named for John Coffee Hays, the Texas Ranger captain who commanded on the San Antonio frontier in the 1840s and later became a sheriff in California. Ten years after it was formed, parts of Hays went into the new county of Blanco. The Census Bureau put the county at roughly 292,029 in 2024, an increase of about a fifth in four years.

Kyle and Buda are the growth story. Both were small railroad towns on the I-35 line until the 2000s, and both have multiplied several times over as Austin's housing market pushed south — Kyle's 2024 estimate is about 65,833, which would put it ahead of San Marcos's resident count within a few years. Dripping Springs, in the northwest on US-290, has done the same on a smaller base. Unincorporated communities include Driftwood, southwest of Dripping Springs, Henly on US-290, and the ranch subdivisions strung along Ranch Road 12 and Fitzhugh Road.

The San Marcos Springs come out of the Edwards Aquifer along the Balcones fault zone and fill Spring Lake, on the Texas State University campus. They are among the largest springs in the state and, unlike the Comal Springs 20 miles south, they have never been recorded as failing completely, even in the drought of the 1950s — which is why the site has been continuously attractive to people for thousands of years.

The constant temperature and clarity support species found nowhere else: Texas wild rice, which grows only in the upper San Marcos River, the Texas blind salamander in the aquifer below, and the fountain darter. The Meadows Center for Water and the Environment runs glass-bottom boats over the spring openings. Downstream, the river runs through Rio Vista Park and past the city, and floating it is a summer institution — as is the periodic argument about how many tubers the river can take.

Texas State University sits on the hill above the springs. Founded in 1899 as a normal school for teachers, it is now one of the largest universities in Texas and the county's biggest employer, and it is the only Texas university to have graduated a president of the United States: Lyndon Johnson took his degree there in 1930.

Ranch Road 12 links the county's two hill towns. Wimberley sits where Cypress Creek meets the Blanco, with a square of shops, a long-running market day and the Blue Hole swimming hole under bald cypress on the creek. Dripping Springs, 20 miles north on US-290, has grown into a commuter town and, since the 2010s, into a cluster of distilleries, breweries and wedding venues on the ranch roads around it.

Jacob's Well, northwest of Wimberley off RM 12, is the spring that feeds Cypress Creek: an artesian mouth in the creek bed opening into a vertical shaft that divers have followed for well over a hundred feet through a series of chambers. It is one of the longest underwater cave systems in the state, it has killed divers who went too far, and it is a straightforward measure of the aquifer's health — it stopped flowing for the first time on record in 2000 and has done so again in later droughts, closing the swimming hole above it.

The Blanco River is the county's other hazard. On Memorial Day weekend in 2015 a storm over the upper watershed sent a wall of water down the narrow limestone channel through Wimberley in the middle of the night; it rose tens of feet in a few hours, destroyed hundreds of houses along the river and killed more than a dozen people. The stripped cypress and the rebuilt bridges along the river road still mark the line it reached.