How far is San Antonio, TX from Buchanan Dam, TX?

The driving distance from San Antonio, TX to Buchanan Dam, TX is about 104 miles (167.3 km), with a travel time of about 02h 14m by car.

  • The straight-line flight distance is about 91 miles (146.4 km).
  • For a round trip, plan for roughly 04h 29m of driving time before adding stops, traffic, or weather delays.
  • A comfortable departure window is usually 8:00 AM to 10:00 AM CDT.
Trip Tools

Reverse, save, or send this route

This route works well as a day trip with time at the destination. Copy the route link, send it to another device, or print a clean version before you head out.

Reverse Route
Quick Snapshot
Road
103.97 mi
02h 14m
Flight
90.99 mi
146.43 km direct

This route works well as a day trip with time at the destination.

Learn Distance

Choose another destination from San Antonio.

Flight Distance

Direct air line
90.99 mi
Kilometers
146.43 km
Flight Time
00h 10m

Driving Distance

Road route
103.97 mi
Kilometers
167.33 km
Drive Time
02h 14m

Gas Cost Calculator

Leave and Arrive Planner

Pick a departure time to see your estimated arrival and same-day return window.

Drive time stays fixed at 02h 14m.

Arrival Snapshot
Arrive in Buchanan Dam
Sat, Apr 18, 10:38 PM CDT
Return by in San Antonio
Sun, Apr 19, 12:53 AM CDT
Useful when you're deciding between a quick errand, a day trip, or a longer stop.
Leave San Antonio
2026-04-18T20:24
Arrive Buchanan Dam
Sat, Apr 18, 10:38 PM CDT
Route Timing
02h 14m
One way by road
Best Departure Window
8:00 AM to 10:00 AM CDT
Aim for a morning departure
Arrive between
10:15 AM to 12:15 PM CDT

A morning start gives you useful time at the destination and keeps the return out of the late evening.

Leave by
2:00 PM CDT
Keeps a same-day return open with about 03h 00m at the destination.
Back in San Antonio
9:30 PM CDT
Morning start is best

You are leaving earlier than the recommended window, which gives you extra margin for breaks and traffic.

Halfway Point

A useful midpoint for breaks, coffee, or meeting in the middle.

Mid-route stop
Blanco
TX

City in Blanco County, Texas, United States

From San Antonio
52.1 mi
01h 07m
To Buchanan Dam
51.9 mi
01h 07m

Route Weather Snapshot

Check the forecast at both ends before you head out.

Origin
81°F
Saturday

Chance Showers And Thunderstorms

Starts
Sat, Apr 18 6:00 AM CDT
Wind
5 to 15 mph ENE
Destination
71°F
Saturday

Slight Chance Showers And Thunderstorms then Showers And Thunderstorms Likely

Starts
Sat, Apr 18 6:00 AM CDT
Wind
5 to 10 mph NW

Driving Route Map

The map below follows the saved road route between San Antonio and Buchanan Dam.

Turn-by-Turn Driving Directions

Step-by-step road directions between San Antonio and Buchanan Dam.

  1. 1

    Start on Dolorosa Street

    44 m · 5 sec · Dolorosa Street

  2. 2

    Continue on West Market Street

    1893 ft · 42 sec · West Market Street

  3. 3

    Continue on East Market Street

    2143 ft · 46 sec · East Market Street

  4. 4

    Turn left

    111 m · 13 sec

  5. 5

    Turn straight onto East Commerce Street

    66 m · 13 sec · East Commerce Street

  6. 6

    Take the ramp sharp left toward US 281 North, I 37 North

    1159 ft · 28 sec

  7. 7

    Merge slight left onto William J Bordelon Freeway

    1.5 km · 1 min · William J Bordelon Freeway

  8. 8

    Continue on McAllister Freeway

    14.9 mi · 18 min · McAllister Freeway

  9. 9

    Keep slight left to continue on US 281 HOV Lane

    2.9 mi · 3 min · US 281 HOV Lane

  10. 10

    Merge slight right

    54.7 mi · 1 hr 4 min

  11. 11

    Turn left onto West Ranch Road 962

    10.5 mi · 14 min · West Ranch Road 962

  12. 12

    At the end of the road, turn left onto West State Highway 71

    3.4 mi · 5 min · West State Highway 71

  13. 13

    Turn right

    2.6 mi · 5 min

  14. 14

    Turn left onto Ranch to Market Road 2900

    5.3 mi · 9 min · Ranch to Market Road 2900

  15. 15

    At the end of the road, turn left

    5.5 mi · 10 min

  16. 16

    Turn right

    2.1 mi · 3 min

  17. 17

    Turn left onto Island Lodges Drive

    43 m · 6 sec · Island Lodges Drive

  18. 18

    Arrive at your destination

    0 m · 1 sec · Island Lodges Drive

Car Route Details

A richer read on the saved driving route between San Antonio and Buchanan Dam.

OSRM road route
Drive Character

Highway-focused drive

Most of the mileage stays on named highways, so the important moments are ramps, exits, merges, and the final local approach.

Directions
18 steps
9 turns on the saved route
Ramps & Exits
3
2 merges, 1 ramps or exits
Navigation Density
17.3 / 100 mi
Decision points by distance
Main Roads
US 281 HOV Lane
57.6 mi · 55%
McAllister Freeway
14.9 mi · 14%
West Ranch Road 962
10.5 mi · 10%
Ranch to Market Road 2900
5.28 mi · 5%
West State Highway 71
3.38 mi · 3%
William J Bordelon Freeway
0.95 mi · 1%
Longest Stretch

US 281 HOV Lane

Merge slight right

54.7 mi · 01h 04m

Route Summary

A quick read on whether this route feels easy, ambitious, or worth planning around.

Trip Read

A comfortable day-trip route

This route works well as a day trip. You can leave in the morning, spend meaningful time at the destination, and still return the same day.

Drive Time
02h 14m
Day trip friendly
Same-Day Return
04h 30m
Round-trip wheel time
Road vs Air
+13 mi
91 mi direct line
Halfway Stop
Blanco
01h 07m from San Antonio
Leave By
2:00 PM CDT
Morning start is best
Weather Watch

Chance Showers And Thunderstorms leaving San Antonio and Slight Chance Showers And Thunderstorms then Showers And Thunderstorms Likely near Buchanan Dam.

Trip Questions

Direct answers travelers usually want before committing to the drive.

How long does it take to drive from San Antonio to Buchanan Dam?

The road trip is about 104 miles (167.3 km) and usually takes 02h 14m in normal driving conditions.

Is this a same-day trip or an overnight route?

This route works well as a day trip. You can leave in the morning, spend meaningful time at the destination, and still return the same day.

What is the halfway point on this route?

Blanco is a useful midpoint, sitting about 52.1 miles from San Antonio and 51.9 miles from Buchanan Dam.

How much longer is the road route than the straight-line distance?

The direct path is about 91 miles (146.4 km), while the road route adds roughly 13 extra miles because roads do not follow the straight air line.

When is the best time to leave for this route?

A good departure window is usually 8:00 AM to 10:00 AM CDT. If you want a more comfortable same-day return, try to leave by 2:00 PM CDT.

How much will gas cost for this route?

Using about 28.3 MPG, regular gas is estimated at $13.87 one way or $27.74 round trip. Estimated CO2 is about 32.6 kg one way.

What should you check before leaving?

Before you leave, expect Chance Showers And Thunderstorms around San Antonio and Slight Chance Showers And Thunderstorms then Showers And Thunderstorms Likely near Buchanan Dam.

Stop Ideas Near Blanco

Useful break, food, and waypoint ideas within about 15 miles of the route midpoint.

Mid-route Guidance
Local place coverage is thin around Blanco, so nearby transit and meeting points are shown instead.
Reviewed stop coverage is still thin around this midpoint, so practical transit waypoints are shown on the right.

Transit and Meeting Points

Useful pickup, handoff, or rendezvous points close to Blanco.

RAIL

San Marcos Station

53 mi away
338 South Guadalupe St.
RAIL

Austin

67 mi away
250 North Lamar Blvd.
RAIL

San Antonio Station

76 mi away
350 Hoefgen Street
RAIL

Taylor

110 mi away
118 East First St.

Flight Path Map

This map shows the direct air route between San Antonio and Buchanan Dam. Straight-line distance: 90.99 mi (146.43 km).

San Antonio

#1 San Antonio

The seventh most populous city in the United States and the center of the San Antonio metropolitan area.

Population1,567,118
Coordinates29.4241200, -98.4936300
Altitude198
CountryUnited States
Buchanan Dam

#2 Buchanan Dam

Place in Texas

Population1,519
Coordinates30.7399000, -98.4311400
Altitude318
CountryUnited States
Start: San Antonio (-98.49363, 29.42412)
End: Buchanan Dam (-98.43114, 30.7399)

Estimated Travel Time

Distance: 167 km by road

SpeedTime
30 mph (48.3 km/h)03h 27m
40 mph (64.37 km/h)02h 35m
50 mph (80.47 km/h)02h 04m
60 mph (96.56 km/h)01h 43m
70 mph (112.65 km/h)01h 29m
80 mph (129 km/h)01h 17m

Fuel, Round Trip and CO2

Estimated fuel cost and emissions for this route.

One-way fuel
3.67 gal
13.89 L · about $13.87
Round trip
$27.74
7.34 gal · 27.78 L
Estimated CO2
32.6 kg one way
Round trip: 65.2 kg / 144 lb CO2, using regular gasoline.
Fuel$/galOne wayRound trip
Regular gas $3.78 $13.87 $27.74
Mid-grade $4.25 $15.60 $31.21
Premium $4.59 $16.85 $33.70
Diesel $3.99 $14.65 $29.31

Assumes 8.3 L/100 km (about 28.3 MPG). CO2 is an estimate and varies by vehicle, fuel blend, traffic, and terrain.

Prices in Texas · Apr 19, 2026

There is no time difference between San Antonio and Buchanan Dam. The current time is 20:24:02.

Distance to Other Cities

Planning a road trip? See the full trip guide on Trip.ovh — stops, fuel costs, weather, and departure timing.

How did we calculate? Place names are translated into coordinates. The Haversine formula calculates straight-line distance; driving distance uses road network data.