Located in Lewis and Clark County, Montana, Tears of the Turtle Cave is a cave. It is part of Bob Marshall Wilderness. It sits roughly 56 km (35 mi) NNE of Seeley Lake.
Tears of the Turtle Cave is located in the Bob Marshall Wilderness in western Montana and is currently the deepest known limestone cave in the United States since passing New Mexico's Lechuguilla Cave in 2014. As of August 2024, the cave is known to be 2,477 feet (755 m) deep and 1.88 miles (3,030 m) long. The cave consists mostly of narrow fissure passages passing over approximately 50 short rope drops. The cave has a temperature of 37 °F (3 °C), and it is muddy and poorly decorated.From the Wikipedia article “Tears of the Turtle Cave”, licensed under CC BY-SA 4.0.
Sunrise & sunset directions
At Tears of the Turtle Cave the sunrise point swings a long way through the year: about 53° (NE) at the June solstice and 125° (SE) in late December. Sunset moves from 308° (NW) in June to 235° (SW) in December, and the midday sun climbs to 66° in summer but only 19° in winter.
| Date | Sunrise | Azimuth | Sunset | Azimuth | Noon sun | Daylight |
|---|---|---|---|---|---|---|
| March equinox (Mar 20) | 7:37 AM | 89° E | 7:46 PM | 271° W | 42° | 12h 09m |
| June solstice (Jun 21) | 5:36 AM | 53° NE | 9:35 PM | 308° NW | 66° | 16h 00m |
| September equinox (Sep 22) | 7:20 AM | 89° E | 7:33 PM | 271° W | 43° | 12h 12m |
| December solstice (Dec 21) | 8:19 AM | 125° SE | 4:44 PM | 235° SW | 19° | 8h 25m |
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
Caves are lit artificially — show caves have fixed lighting, so a fast lens and high ISO beat flash, which flattens formations.
| Month (15th) | Blue hour starts | Sunrise | Golden hour ends | Golden hour starts | Sunset | Blue hour ends | Daylight |
|---|---|---|---|---|---|---|---|
| January | 7:43 AM | 8:17 AM | 9:08 AM | 4:18 PM | 5:09 PM | 5:43 PM | 8h 51m |
| February | 7:08 AM | 7:40 AM | 8:24 AM | 5:13 PM | 5:56 PM | 6:28 PM | 10h 17m |
| March | 7:16 AM | 7:47 AM | 8:28 AM | 6:58 PM | 7:39 PM | 8:09 PM | 11h 52m |
| April | 6:12 AM | 6:45 AM | 7:26 AM | 7:41 PM | 8:23 PM | 8:55 PM | 13h 38m |
| May | 5:19 AM | 5:56 AM | 6:41 AM | 8:19 PM | 9:04 PM | 9:41 PM | 15h 08m |
| June | 4:55 AM | 5:35 AM | 6:24 AM | 8:45 PM | 9:33 PM | 10:14 PM | 15h 58m |
| July | 5:12 AM | 5:51 AM | 6:38 AM | 8:41 PM | 9:28 PM | 10:07 PM | 15h 37m |
| August | 5:56 AM | 6:30 AM | 7:12 AM | 8:04 PM | 8:47 PM | 9:21 PM | 14h 18m |
| September | 6:40 AM | 7:11 AM | 7:52 AM | 7:06 PM | 7:47 PM | 8:18 PM | 12h 36m |
| October | 7:21 AM | 7:52 AM | 8:35 AM | 6:04 PM | 6:46 PM | 7:17 PM | 10h 54m |
| November | 7:06 AM | 7:39 AM | 8:27 AM | 4:10 PM | 4:58 PM | 5:31 PM | 9h 19m |
| December | 7:40 AM | 8:16 AM | 9:08 AM | 3:50 PM | 4:42 PM | 5:18 PM | 8h 27m |
Local time (America/Denver), 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 Tears of the Turtle Cave, the Milky Way core is visible in a dark sky from April through August. June gives the longest window (about 1.7 hours on a moonless night), and the core peaks around 13° 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 | — | -6° | — |
| February | Below 10° in darkness | — | 5° | — |
| March | Below 10° in darkness | — | 9° | — |
| April | 4:08 AM – 4:38 AM | 0.5 | 12° | SSE → SSE |
| May | 2:09 AM – 3:29 AM | 1.3 | 13° | SSE → S |
| June | 12:43 AM – 2:23 AM | 1.7 | 13° | SSE → S |
| July | 12:12 AM – 1:22 AM | 1.2 | 13° | S → SSW |
| August | 10:52 PM – 11:22 PM | 0.5 | 12° | SSW → SSW |
| September | Below 10° in darkness | — | 9° | — |
| October | Below 10° in darkness | — | 5° | — |
| November | Below 10° in darkness | — | -4° | — |
| December | Below 10° in darkness | — | -20° | — |
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 ≈ 21.93 mag/arcsec². Aurora needs roughly Kp 4.0+ to show low on the northern horizon here.
Weather & best season
Long-term NASA satellite data for this area show July as the clearest month (about 36% average cloud cover) and March as the cloudiest (73%). July is the warmest month and December 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 | 37 | 45 | 65 | 71 | 80 | 90 | 99 | 95 | 87 | 77 | 59 | 38 |
| Low °F | -29 | -36 | -27 | -7 | 20 | 27 | 35 | 35 | 20 | -10 | -15 | -31 |
| Precip. (in) | 4.1 | 3.7 | 3.6 | 3.4 | 3.4 | 3.7 | 1.1 | 1.4 | 1.9 | 3.0 | 3.6 | 3.8 |
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 cave
- Use manual focus with focus peaking in low light.
- Never touch formations — skin oils stop their growth.
- Follow White-nose Syndrome decontamination rules where posted to protect bats.
- Many show caves restrict tripods on tours; ask in advance or bring a small beanbag.
- Shoot RAW to keep the most latitude for high-contrast sunrise and sunset scenes.
Season: Cave interiors stay at a constant temperature year-round; summer tours fill up, so book ahead.
Suggested gear: Fast lens (f/1.8–f/2.8), High-ISO camera, Small beanbag. Work out exposures with the depth of field, ND filter and NPF rule calculators.
Permits, drones & access
Drones: Drones may not take off from or land in federally designated wilderness, where mechanized equipment is prohibited under the Wilderness Act.
Nearby photo spots
Other locations within 25 km of Tears of the Turtle Cave, closest first.
WaterfallWaterfall
Wilderness AreaWaterfallCampgrounds nearby (Recreation.gov)
FAQ
When is the best time to photograph Tears of the Turtle Cave?
What time is golden hour at Tears of the Turtle Cave?
Where does the sun rise and set at Tears of the Turtle Cave?
Can you see the Milky Way from Tears of the Turtle Cave?
Do you need a permit to photograph at Tears of the Turtle Cave?
How far is Tears of the Turtle Cave from Seeley Lake?
Sources
Location data: Wikidata, Wikipedia. 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.