Minnetonka Cave is a cave in Bear Lake County, Idaho. It sits roughly 30 km (18 mi) E of Preston.
Minnetonka Cave is one of the larger limestone caves in the state of Idaho. It is located in Cache National Forest in Bear Lake County, Idaho, United States, above the village of St. Charles (located at the north end of Bear Lake). "Minnetonka" is a misunderstanding of the words Mni and Tanka, derived from one of three Indigenous dialects: Dakota, Lakota or Nakota. "Mni Tanka", pronounced (Mini-Tah-"nasal n"-Kah) translates into "Big/Large Water". Tours through the cave are offered from Memorial Day (weather permitting) through Labor Day by Aud-Di Recreational Services, the concessionaire that holds the special use permit from the United States Forest Service. The half-mile route through the cave is lined with stalactites and stalagmites. The cave is a hibernaculum to five different species of bats. One species, the Townsend's Big-eared Bat (Corynorhinus townsendii), while not on...From the Wikipedia article “Minnetonka Cave”, licensed under CC BY-SA 4.0.
Sunrise & sunset directions
At Minnetonka Cave the sunrise point swings a long way through the year: about 57° (ENE) at the June solstice and 122° (ESE) in late December. Sunset moves from 303° (WNW) in June to 239° (WSW) in December, and the midday sun climbs to 71° in summer but only 24° in winter.
| Date | Sunrise | Azimuth | Sunset | Azimuth | Noon sun | Daylight |
|---|---|---|---|---|---|---|
| March equinox (Mar 20) | 7:30 AM | 90° E | 7:38 PM | 271° W | 48° | 12h 08m |
| June solstice (Jun 21) | 5:51 AM | 57° ENE | 9:06 PM | 303° WNW | 71° | 15h 15m |
| September equinox (Sep 22) | 7:14 AM | 89° E | 7:25 PM | 271° W | 48° | 12h 11m |
| December solstice (Dec 21) | 7:52 AM | 122° ESE | 4:58 PM | 239° WSW | 24° | 9h 06m |
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 | 7:22 AM | 7:53 AM | 8:36 AM | 4:36 PM | 5:20 PM | 5:51 PM | 9h 27m |
| February | 6:54 AM | 7:23 AM | 8:02 AM | 5:20 PM | 5:59 PM | 6:28 PM | 10h 36m |
| March | 7:11 AM | 7:39 AM | 8:16 AM | 6:56 PM | 7:33 PM | 8:01 PM | 11h 54m |
| April | 6:17 AM | 6:46 AM | 7:24 AM | 7:30 PM | 8:07 PM | 8:36 PM | 13h 21m |
| May | 5:34 AM | 6:06 AM | 6:46 AM | 8:00 PM | 8:40 PM | 9:12 PM | 14h 34m |
| June | 5:16 AM | 5:50 AM | 6:33 AM | 8:22 PM | 9:04 PM | 9:39 PM | 15h 14m |
| July | 5:31 AM | 6:04 AM | 6:45 AM | 8:20 PM | 9:01 PM | 9:35 PM | 14h 57m |
| August | 6:05 AM | 6:35 AM | 7:13 AM | 7:50 PM | 8:28 PM | 8:58 PM | 13h 54m |
| September | 6:39 AM | 7:07 AM | 7:44 AM | 7:01 PM | 7:37 PM | 8:06 PM | 12h 30m |
| October | 7:11 AM | 7:39 AM | 8:17 AM | 6:08 PM | 6:46 PM | 7:14 PM | 11h 07m |
| November | 6:47 AM | 7:17 AM | 7:59 AM | 4:24 PM | 5:06 PM | 5:36 PM | 9h 49m |
| December | 7:17 AM | 7:48 AM | 8:33 AM | 4:11 PM | 4:56 PM | 5:28 PM | 9h 08m |
Local time (America/Boise), 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 Minnetonka Cave, the Milky Way core is visible in a dark sky from March through September. June gives the longest window (about 4.3 hours on a moonless night), and the core peaks around 19° above the southern horizon. Our light-pollution model puts the sky at about Bortle 2 (typical truly dark site), which is excellent for astrophotography.
| Month | Core visible (15th) | Hours | Max altitude | Direction |
|---|---|---|---|---|
| January | Below 10° in darkness | — | -3° | — |
| February | Below 10° in darkness | — | 10° | — |
| March | 5:06 AM – 5:56 AM | 0.8 | 15° | SSE → SSE |
| April | 2:58 AM – 4:58 AM | 2.0 | 19° | SE → S |
| May | 12:57 AM – 4:07 AM | 3.2 | 19° | SE → S |
| June | 11:16 PM – 3:36 AM | 4.3 | 19° | SSE → SSW |
| July | 11:06 PM – 2:16 AM | 3.2 | 19° | S → SW |
| August | 10:15 PM – 12:15 AM | 2.0 | 18° | S → SW |
| September | 9:12 PM – 10:12 PM | 1.0 | 15° | SSW → SW |
| October | Below 10° in darkness | — | 10° | — |
| 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: 2 Bortle 2 — Typical truly dark site. The summer Milky Way shows rich structure; clouds look like black holes in the stars. Modeled zenith brightness ≈ 21.75 mag/arcsec². Aurora needs roughly Kp 7.0+ 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 35% average cloud cover) and December 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 | 35 | 43 | 63 | 74 | 83 | 89 | 96 | 94 | 86 | 78 | 61 | 43 |
| Low °F | -24 | -19 | -14 | -6 | 17 | 22 | 35 | 32 | 22 | 2 | -18 | -24 |
| Precip. (in) | 2.5 | 2.6 | 2.3 | 2.5 | 2.5 | 1.7 | 0.7 | 1.1 | 1.7 | 1.9 | 2.3 | 2.8 |
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
- 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.
- Use manual focus with focus peaking in low light.
- Never touch formations — skin oils stop their growth.
- 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.
Nearby photo spots
Other locations within 25 km of Minnetonka Cave, closest first.
State Park
Lake
National Wildlife Refuge
Scenic Viewpoint
Mountain Peak
LakeCampgrounds nearby (Recreation.gov)
- Porcupine (Id)868 m · reservable
- Cloverleaf Campground1.4 km (0.8 mi) · reservable
- North Fork Campground - St. Charles Canyon1.5 km (0.9 mi) · reservable
- Davis Canyon Campground3.3 km (2.1 mi) · reservable
- Egan Basin Guard Station5.7 km (3.5 mi) · reservable
FAQ
When is the best time to photograph Minnetonka Cave?
What time is golden hour at Minnetonka Cave?
Where does the sun rise and set at Minnetonka Cave?
Can you see the Milky Way from Minnetonka Cave?
Do you need a permit to photograph at Minnetonka Cave?
How far is Minnetonka Cave from Preston?
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.