Southeast Rim Keyhole is a natural arch in Brewster County, Texas at about 2,062 m (6,765 ft) above sea level. It lies in or next to Big Bend National Park, so park hours, fees and rules apply. The nearest town is Alpine, about 130 km (81 mi) away (Southeast Rim Keyhole lies SSE of town).
Sunrise & sunset directions
At Southeast Rim Keyhole the sunrise point swings a long way through the year: about 62° (ENE) at the June solstice and 117° (ESE) in late December. Sunset moves from 298° (WNW) in June to 244° (WSW) in December, and the midday sun climbs to 84° in summer but only 37° in winter.
| Date | Sunrise | Azimuth | Sunset | Azimuth | Noon sun | Daylight |
|---|---|---|---|---|---|---|
| March equinox (Mar 20) | 7:58 AM | 90° E | 8:05 PM | 271° W | 61° | 12h 07m |
| June solstice (Jun 21) | 6:55 AM | 62° ENE | 8:56 PM | 298° WNW | 84° | 14h 01m |
| September equinox (Sep 22) | 7:42 AM | 89° E | 7:51 PM | 271° W | 61° | 12h 09m |
| December solstice (Dec 21) | 7:44 AM | 117° ESE | 6:00 PM | 244° WSW | 37° | 10h 16m |
Azimuth is measured clockwise from true north (90° = east, 270° = west). Computed for 2026; values change by less than a degree from year to year.
Golden hour & blue hour by month
Arches glow when reflected light bounces off nearby rock — the underside of an arch often turns bright orange just after sunrise or before sunset.
| Month (15th) | Blue hour starts | Sunrise | Golden hour ends | Golden hour starts | Sunset | Blue hour ends | Daylight |
|---|---|---|---|---|---|---|---|
| January | 7:23 AM | 7:49 AM | 8:24 AM | 5:43 PM | 6:17 PM | 6:43 PM | 10h 29m |
| February | 7:09 AM | 7:33 AM | 8:06 AM | 6:11 PM | 6:43 PM | 7:08 PM | 11h 10m |
| March | 7:40 AM | 8:04 AM | 8:35 AM | 7:31 PM | 8:02 PM | 8:26 PM | 11h 58m |
| April | 7:03 AM | 7:28 AM | 7:59 AM | 7:48 PM | 8:20 PM | 8:44 PM | 12h 52m |
| May | 6:36 AM | 7:02 AM | 7:35 AM | 8:05 PM | 8:39 PM | 9:05 PM | 13h 37m |
| June | 6:27 AM | 6:54 AM | 7:29 AM | 8:20 PM | 8:55 PM | 9:22 PM | 14h 00m |
| July | 6:38 AM | 7:04 AM | 7:39 AM | 8:21 PM | 8:55 PM | 9:21 PM | 13h 50m |
| August | 6:57 AM | 7:22 AM | 7:55 AM | 8:02 PM | 8:35 PM | 9:00 PM | 13h 12m |
| September | 7:15 AM | 7:39 AM | 8:10 AM | 7:28 PM | 8:00 PM | 8:24 PM | 12h 21m |
| October | 7:31 AM | 7:55 AM | 8:27 AM | 6:52 PM | 7:24 PM | 7:48 PM | 11h 29m |
| November | 6:53 AM | 7:18 AM | 7:52 AM | 5:25 PM | 6:00 PM | 6:25 PM | 10h 42m |
| December | 7:14 AM | 7:41 AM | 8:16 AM | 5:22 PM | 5:58 PM | 6:24 PM | 10h 17m |
Local time (America/Chicago), including daylight saving time. Golden hour runs from about −4° to +6° solar altitude, so the morning golden hour begins during blue hour, before sunrise.
Milky Way & night sky
From Southeast Rim Keyhole, the Milky Way core is visible in a dark sky from February through October. June gives the longest window (about 6.7 hours on a moonless night), and the core peaks around 32° above the southern horizon. Our light-pollution model puts the sky at about Bortle 1 (excellent dark-sky site), which is excellent for astrophotography.
| Month | Core visible (15th) | Hours | Max altitude | Direction |
|---|---|---|---|---|
| January | Below 10° in darkness | — | 2° | — |
| February | 5:13 AM – 6:03 AM | 0.8 | 19° | SE → SE |
| March | 4:21 AM – 6:41 AM | 2.3 | 29° | SE → SSE |
| April | 2:22 AM – 6:02 AM | 3.7 | 32° | SE → S |
| May | 12:18 AM – 5:28 AM | 5.2 | 32° | SE → SSW |
| June | 10:30 PM – 5:10 AM | 6.7 | 32° | SE → SW |
| July | 10:27 PM – 3:47 AM | 5.3 | 32° | SSE → SW |
| August | 10:00 PM – 1:50 AM | 3.8 | 32° | S → SW |
| September | 9:19 PM – 11:49 PM | 2.5 | 29° | SSW → SW |
| October | 8:43 PM – 9:43 PM | 1.0 | 20° | SW → SW |
| November | Below 10° in darkness | — | 5° | — |
| December | Below 10° in darkness | — | -18° | — |
Window when the galactic core is at least 10° high during astronomical darkness on the 15th of each month. Pick nights within a few days of the new moon. Plan exact nights with the Milky Way planner.
Estimated sky darkness: 1 Bortle 1 — Excellent dark-sky site. The Milky Way casts faint shadows; zodiacal light and airglow are obvious. Modeled zenith brightness ≈ 21.95 mag/arcsec².
Weather & best season
Long-term NASA satellite data for this area show October as the clearest month (about 29% average cloud cover) and July as the cloudiest (46%). June is the warmest month and January the coldest, which matters for gear, snow access and how long batteries last at night.
Average cloud cover (%)
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| High °F | 83 | 93 | 96 | 102 | 108 | 110 | 109 | 107 | 104 | 98 | 91 | 83 |
| Low °F | 20 | 11 | 22 | 35 | 38 | 61 | 62 | 60 | 51 | 30 | 21 | 18 |
| Precip. (in) | 0.5 | 0.4 | 0.4 | 0.5 | 1.1 | 1.4 | 1.9 | 1.9 | 1.8 | 1.0 | 0.6 | 0.5 |
Monthly climatology for the surrounding 1° grid cell from NASA POWER (MERRA-2). Mountain sites can be colder and cloudier than the cell average.
Photography tips for this natural arch
- Never climb on arches; many are fragile and climbing is prohibited on park lands.
- Midday sun creates hard shadows, but can light the underside through reflection in narrow canyons.
- Frame distant features through the opening of the arch for a natural window.
- At night, arches make classic Milky Way foregrounds; low-level lighting or blue hour exposures keep the rock detailed.
- Use a wide lens and get close to emphasize the span against the sky.
- Bring a spare battery — cold weather and long exposures drain them fast.
Season: Spring and autumn offer mild temperatures in desert arch country; summer heat is extreme at midday.
Suggested gear: Ultra-wide lens, Tripod, Headlamp, Plenty of water. Work out exposures with the depth of field, ND filter and NPF rule calculators.
Permits, drones & access
National Park Service rules. Under federal law (54 U.S.C. 100905), still photography in National Park Service areas needs a permit only when it (1) takes place where members of the public are not allowed, (2) uses models, sets or props that are not part of the location's natural or cultural resources or administrative facilities, or (3) would cause the park to incur additional administrative costs to monitor the activity. Ordinary visitor and most landscape photography needs no permit. Commercial filming rules are separate and have changed in recent years — confirm current requirements with the park before a paid shoot.
Drones: Launching, landing or operating unmanned aircraft (drones) is prohibited in National Park Service units under a 2014 Superintendent's closure (36 CFR 1.5), except where a park has issued specific written approval. Flying from outside the boundary over park land can also violate park rules and disturb wildlife.
Nearby photo spots
Other locations within 25 km of Southeast Rim Keyhole, closest first.
Mountain Peak
Dark Sky Place
Waterfall
Scenic Viewpoint
Natural Arch
Ghost TownScenic ViewpointNatural ArchCampgrounds nearby (Recreation.gov)
- Chisos Basin Group Campground (Big Bend, Tx)4.9 km (3.0 mi) · reservable
- Chisos Basin Campground (Big Bend, Tx)4.9 km (3.0 mi) · reservable
- Big Bend Backcountry Camping12.5 km (7.7 mi) · reservable
- Cottonwood (Big Bend, Tx)26 km (16 mi) · reservable
FAQ
When is the best time to photograph Southeast Rim Keyhole?
What time is golden hour at Southeast Rim Keyhole?
Where does the sun rise and set at Southeast Rim Keyhole?
Can you see the Milky Way from Southeast Rim Keyhole?
Do you need a permit to photograph at Southeast Rim Keyhole?
How far is Southeast Rim Keyhole from Alpine?
Sources
Location data: USGS GNIS / GeoNames. Sun, moon and Milky Way times are computed by LWPhoto Atlas for 2026. Climate: NASA POWER. Sky darkness is a population-based estimate (Walker's law), not a measurement. See data sources & licenses.