Located in Rockcastle County, Kentucky, Great Saltpetre Cave is a cave. The nearest town is Mount Vernon, about 4.9 km (3.0 mi) away (Great Saltpetre Cave lies ENE of town).
The Great Saltpetre Cave is a notable limestone cave located in Rockcastle County in southeastern Kentucky. During the War of 1812, it served as an important source of saltpeter, a vital component of gunpowder Also known as black powder. The cave was listed on the National Register of Historic Places in 2013, and is within the boundary of the Daniel Boone National Forest. Other names include Kincaid's Cave and The Great Cave on Crooked Creek. Robert Baker discovered the cave in the late eighteenth century. A stream ran through the cave, and was wide enough so that oxcarts could be used to bring the saltpeter above ground. However, torchlights had to be used to light the cave so that workers could mine the saltpeter from the ground.From the Wikipedia article “Great Saltpetre Cave”, licensed under CC BY-SA 4.0.
Sunrise & sunset directions
At Great Saltpetre Cave the sunrise point swings a long way through the year: about 59° (ENE) at the June solstice and 119° (ESE) in late December. Sunset moves from 301° (WNW) in June to 241° (WSW) in December, and the midday sun climbs to 76° in summer but only 29° in winter.
| Date | Sunrise | Azimuth | Sunset | Azimuth | Noon sun | Daylight |
|---|---|---|---|---|---|---|
| March equinox (Mar 20) | 7:42 AM | 90° E | 7:49 PM | 271° W | 53° | 12h 08m |
| June solstice (Jun 21) | 6:17 AM | 59° ENE | 9:02 PM | 301° WNW | 76° | 14h 44m |
| September equinox (Sep 22) | 7:26 AM | 89° E | 7:36 PM | 271° W | 53° | 12h 10m |
| December solstice (Dec 21) | 7:49 AM | 119° ESE | 5:24 PM | 241° WSW | 29° | 9h 35m |
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 | 7:23 AM | 7:51 AM | 8:30 AM | 5:04 PM | 5:43 PM | 6:12 PM | 9h 52m |
| February | 7:01 AM | 7:27 AM | 8:04 AM | 5:41 PM | 6:17 PM | 6:44 PM | 10h 50m |
| March | 7:23 AM | 7:49 AM | 8:24 AM | 7:10 PM | 7:45 PM | 8:11 PM | 11h 56m |
| April | 6:36 AM | 7:03 AM | 7:38 AM | 7:37 PM | 8:12 PM | 8:39 PM | 13h 09m |
| May | 6:00 AM | 6:29 AM | 7:06 AM | 8:02 PM | 8:40 PM | 9:09 PM | 14h 10m |
| June | 5:46 AM | 6:17 AM | 6:56 AM | 8:21 PM | 9:00 PM | 9:31 PM | 14h 43m |
| July | 5:59 AM | 6:29 AM | 7:07 AM | 8:20 PM | 8:59 PM | 9:29 PM | 14h 30m |
| August | 6:26 AM | 6:54 AM | 7:30 AM | 7:55 PM | 8:31 PM | 8:59 PM | 13h 37m |
| September | 6:54 AM | 7:20 AM | 7:54 AM | 7:12 PM | 7:47 PM | 8:13 PM | 12h 27m |
| October | 7:19 AM | 7:46 AM | 8:21 AM | 6:26 PM | 7:01 PM | 7:28 PM | 11h 16m |
| November | 6:50 AM | 7:17 AM | 7:56 AM | 4:50 PM | 5:28 PM | 5:56 PM | 10h 11m |
| December | 7:16 AM | 7:45 AM | 8:26 AM | 4:41 PM | 5:21 PM | 5:50 PM | 9h 36m |
Local time (America/New York), 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 Great Saltpetre Cave, the Milky Way core is visible in a dark sky from March through September. June gives the longest window (about 5.5 hours on a moonless night), and the core peaks around 24° above the southern horizon. Our light-pollution model puts the sky at about Bortle 3 (rural sky), good enough for detailed Milky Way images.
| Month | Core visible (15th) | Hours | Max altitude | Direction |
|---|---|---|---|---|
| January | Below 10° in darkness | — | -1° | — |
| February | 5:35 AM – 5:55 AM | 0.3 | 13° | SE → SE |
| March | 4:41 AM – 6:11 AM | 1.5 | 20° | SE → SSE |
| April | 2:44 AM – 5:24 AM | 2.7 | 24° | SE → S |
| May | 12:43 AM – 4:43 AM | 4.0 | 24° | SE → SSW |
| June | 10:53 PM – 4:23 AM | 5.5 | 24° | SE → SW |
| July | 10:47 PM – 2:57 AM | 4.2 | 24° | SSE → SW |
| August | 10:07 PM – 12:57 AM | 2.8 | 24° | S → SW |
| September | 9:15 PM – 10:55 PM | 1.7 | 21° | SSW → SW |
| October | 8:28 PM – 8:48 PM | 0.3 | 14° | SW → SW |
| November | Below 10° in darkness | — | 1° | — |
| December | Below 10° in darkness | — | -19° | — |
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: 3 Bortle 3 — Rural sky. Some light domes sit on the horizon, but the Milky Way still looks complex overhead. Modeled zenith brightness ≈ 21.57 mag/arcsec². Aurora needs roughly Kp 8.0+ to show low on the northern horizon here.
Weather & best season
Long-term NASA satellite data for this area show September as the clearest month (about 48% average cloud cover) and February as the cloudiest (72%). July 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 | 70 | 73 | 82 | 83 | 91 | 105 | 104 | 103 | 100 | 98 | 83 | 71 |
| Low °F | -2 | -3 | -1 | 22 | 29 | 44 | 52 | 48 | 38 | 25 | 4 | 2 |
| Precip. (in) | 3.5 | 4.3 | 4.1 | 4.9 | 4.8 | 4.4 | 5.1 | 3.6 | 3.6 | 3.6 | 3.6 | 4.4 |
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.
- Tell someone where you're going in remote areas and carry the ten essentials.
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.
Nearby photo spots
Other locations within 25 km of Great Saltpetre Cave, closest first.
FAQ
When is the best time to photograph Great Saltpetre Cave?
What time is golden hour at Great Saltpetre Cave?
Where does the sun rise and set at Great Saltpetre Cave?
Can you see the Milky Way from Great Saltpetre Cave?
Do you need a permit to photograph at Great Saltpetre Cave?
How far is Great Saltpetre Cave from Mount Vernon?
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.