Located in Carter County, Kentucky, Saltpeter Cave is a cave. It sits roughly 9.5 km (5.9 mi) NNE of Olive Hill. It is listed on the National Register of Historic Places.
Saltpeter Cave, in Carter Caves State Resort Park near Olive Hill, Kentucky. It was listed on the National Register of Historic Places in 2001. It has also been known as Swingle's Cave and as Swindell's Cave. It is a limestone cave with 3.05 kilometres (1.90 mi) of measured length. It has served as a saltpeter, or niter, mine, by the early 1800s. It has been believed, by local tradition, that niter mined from the cave was used to make gunpowder for the War of 1812, including supplying for the 1815 Battle of New Orleans. The cave entrance is gated by a "limestone block and iron bar structure, resembling a jail cell", which was built in the mid-1900s. The cave was developed for use by bats. The cave is unique in that it is a hibernaculum for the endangered Indiana Bat in the winter months. It is open for cave tours during the summer, from Memorial Day to Labor Day.From the Wikipedia article “Saltpeter Cave”, licensed under CC BY-SA 4.0.
Sunrise & sunset directions
At Saltpeter Cave the sunrise point swings a long way through the year: about 59° (ENE) at the June solstice and 120° (ESE) in late December. Sunset moves from 301° (WNW) in June to 240° (WSW) in December, and the midday sun climbs to 75° in summer but only 28° in winter.
| Date | Sunrise | Azimuth | Sunset | Azimuth | Noon sun | Daylight |
|---|---|---|---|---|---|---|
| March equinox (Mar 20) | 7:37 AM | 90° E | 7:45 PM | 271° W | 51° | 12h 08m |
| June solstice (Jun 21) | 6:10 AM | 59° ENE | 9:00 PM | 301° WNW | 75° | 14h 51m |
| September equinox (Sep 22) | 7:21 AM | 89° E | 7:31 PM | 271° W | 52° | 12h 10m |
| December solstice (Dec 21) | 7:47 AM | 120° ESE | 5:16 PM | 240° WSW | 28° | 9h 29m |
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 | 7:20 AM | 7:49 AM | 8:29 AM | 4:56 PM | 5:36 PM | 6:05 PM | 9h 47m |
| February | 6:57 AM | 7:24 AM | 8:01 AM | 5:34 PM | 6:11 PM | 6:38 PM | 10h 47m |
| March | 7:18 AM | 7:45 AM | 8:20 AM | 7:05 PM | 7:40 PM | 8:06 PM | 11h 55m |
| April | 6:30 AM | 6:57 AM | 7:33 AM | 7:33 PM | 8:09 PM | 8:36 PM | 13h 12m |
| May | 5:52 AM | 6:22 AM | 7:00 AM | 8:00 PM | 8:37 PM | 9:07 PM | 14h 15m |
| June | 5:37 AM | 6:09 AM | 6:49 AM | 8:19 PM | 8:59 PM | 9:30 PM | 14h 50m |
| July | 5:51 AM | 6:21 AM | 7:00 AM | 8:18 PM | 8:57 PM | 9:27 PM | 14h 35m |
| August | 6:20 AM | 6:48 AM | 7:24 AM | 7:52 PM | 8:28 PM | 8:56 PM | 13h 40m |
| September | 6:48 AM | 7:15 AM | 7:50 AM | 7:08 PM | 7:42 PM | 8:09 PM | 12h 28m |
| October | 7:15 AM | 7:42 AM | 8:18 AM | 6:20 PM | 6:56 PM | 7:23 PM | 11h 14m |
| November | 6:47 AM | 7:15 AM | 7:54 AM | 4:42 PM | 5:21 PM | 5:49 PM | 10h 06m |
| December | 7:14 AM | 7:43 AM | 8:25 AM | 4:32 PM | 5:14 PM | 5:43 PM | 9h 30m |
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 Saltpeter Cave, the Milky Way core is visible in a dark sky from March through September. June gives the longest window (about 5.2 hours on a moonless night), and the core peaks around 23° 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 | — | -2° | — |
| February | 5:29 AM – 5:49 AM | 0.3 | 12° | SE → SE |
| March | 4:48 AM – 6:08 AM | 1.3 | 19° | SE → SSE |
| April | 2:43 AM – 5:13 AM | 2.5 | 22° | SE → S |
| May | 12:44 AM – 4:34 AM | 3.8 | 23° | SE → SSW |
| June | 10:56 PM – 4:06 AM | 5.2 | 23° | SE → SSW |
| July | 10:49 PM – 2:39 AM | 3.8 | 23° | SSE → SW |
| August | 10:07 PM – 12:37 AM | 2.5 | 22° | S → SW |
| September | 9:12 PM – 10:42 PM | 1.5 | 19° | SSW → SW |
| October | 8:23 PM – 8:43 PM | 0.3 | 13° | SW → SW |
| November | Below 10° in darkness | — | 0° | — |
| 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 ≈ 21.37 mag/arcsec². Aurora needs roughly Kp 7.5+ 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 47% average cloud cover) and January as the cloudiest (75%). 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 | 86 | 97 | 103 | 109 | 103 | 102 | 96 | 82 | 71 |
| Low °F | -4 | -6 | 8 | 21 | 28 | 41 | 52 | 50 | 39 | 26 | 11 | 4 |
| Precip. (in) | 2.9 | 3.5 | 3.8 | 4.4 | 4.7 | 4.2 | 4.5 | 3.1 | 3.4 | 3.6 | 3.1 | 3.7 |
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 Saltpeter Cave, closest first.
Cave
State Park
Covered Bridge
WaterfallCampgrounds nearby (Recreation.gov)
FAQ
When is the best time to photograph Saltpeter Cave?
What time is golden hour at Saltpeter Cave?
Where does the sun rise and set at Saltpeter Cave?
Can you see the Milky Way from Saltpeter Cave?
Do you need a permit to photograph at Saltpeter Cave?
How far is Saltpeter Cave from Olive Hill?
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.