Indian Grinding Rock State Historic Park is a state park in Amador County, California. It sits roughly 3.6 km (2.2 mi) NNW of Sutter Creek. It is listed on the National Register of Historic Places.
Indian Grinding Rock State Historic Park is a California State Park, preserving an outcropping of marbleized limestone with some 1,185 mortar holes—the largest collection of bedrock mortars in North America. It is located in the Sierra Nevada foothills, about 9 miles (14 km) northeast of Jackson. The park is nestled in a little valley 2,400 feet (732 m) above sea level, with open meadows and large specimens of valley oak that once provided the Miwok peoples of this area with an ample supply of acorns. The 135-acre (55 ha) park was established in 1962 and listed on the National Register of Historic Places in 1971.From the Wikipedia article “Indian Grinding Rock State Historic Park”, licensed under CC BY-SA 4.0.
Sunrise & sunset directions
At Indian Grinding Rock State Historic Park 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) | 7:08 AM | 90° E | 7:15 PM | 271° W | 51° | 12h 08m |
| June solstice (Jun 21) | 5:40 AM | 59° ENE | 8:31 PM | 301° WNW | 75° | 14h 51m |
| September equinox (Sep 22) | 6:52 AM | 89° E | 7:02 PM | 271° W | 52° | 12h 10m |
| December solstice (Dec 21) | 7:18 AM | 120° ESE | 4:47 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
State parks often protect a signature feature — a gorge, lake or overlook — that is best in early morning before visitors and harsh light arrive.
| Month (15th) | Blue hour starts | Sunrise | Golden hour ends | Golden hour starts | Sunset | Blue hour ends | Daylight |
|---|---|---|---|---|---|---|---|
| January | 6:51 AM | 7:20 AM | 8:00 AM | 4:27 PM | 5:07 PM | 5:36 PM | 9h 47m |
| February | 6:28 AM | 6:55 AM | 7:32 AM | 5:05 PM | 5:42 PM | 6:09 PM | 10h 47m |
| March | 6:49 AM | 7:15 AM | 7:50 AM | 6:36 PM | 7:11 PM | 7:37 PM | 11h 55m |
| April | 6:00 AM | 6:28 AM | 7:03 AM | 7:04 PM | 7:40 PM | 8:07 PM | 13h 12m |
| May | 5:23 AM | 5:53 AM | 6:30 AM | 7:31 PM | 8:08 PM | 8:38 PM | 14h 15m |
| June | 5:08 AM | 5:40 AM | 6:19 AM | 7:50 PM | 8:29 PM | 9:01 PM | 14h 50m |
| July | 5:21 AM | 5:52 AM | 6:31 AM | 7:49 PM | 8:27 PM | 8:58 PM | 14h 35m |
| August | 5:50 AM | 6:19 AM | 6:55 AM | 7:22 PM | 7:59 PM | 8:27 PM | 13h 40m |
| September | 6:19 AM | 6:46 AM | 7:21 AM | 6:38 PM | 7:13 PM | 7:40 PM | 12h 27m |
| October | 6:46 AM | 7:13 AM | 7:49 AM | 5:51 PM | 6:26 PM | 6:53 PM | 11h 14m |
| November | 6:18 AM | 6:46 AM | 7:25 AM | 4:13 PM | 4:52 PM | 5:20 PM | 10h 06m |
| December | 6:44 AM | 7:14 AM | 7:56 AM | 4:03 PM | 4:44 PM | 5:14 PM | 9h 30m |
Local time (America/Los Angeles), 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 Indian Grinding Rock State Historic Park, 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 4 (rural / suburban transition), good enough for detailed Milky Way images.
| Month | Core visible (15th) | Hours | Max altitude | Direction |
|---|---|---|---|---|
| January | Below 10° in darkness | — | -2° | — |
| February | 5:00 AM – 5:20 AM | 0.3 | 13° | SE → SE |
| March | 4:19 AM – 5:39 AM | 1.3 | 19° | SE → SSE |
| April | 2:14 AM – 4:44 AM | 2.5 | 22° | SE → S |
| May | 12:15 AM – 3:55 AM | 3.7 | 23° | SE → S |
| June | 10:27 PM – 3:37 AM | 5.2 | 23° | SE → SSW |
| July | 10:20 PM – 2:10 AM | 3.8 | 23° | SSE → SW |
| August | 9:37 PM – 12:07 AM | 2.5 | 22° | S → SW |
| September | 8:43 PM – 10:13 PM | 1.5 | 19° | SSW → SW |
| October | 7:54 PM – 8:14 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: 4 Bortle 4 — Rural / suburban transition. Light domes are visible in several directions; the Milky Way is clear but lacks detail near the horizon. Modeled zenith brightness ≈ 20.78 mag/arcsec².
Weather & best season
Long-term NASA satellite data for this area show August as the clearest month (about 14% average cloud cover) and December as the cloudiest (62%). 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 | 72 | 70 | 75 | 84 | 97 | 104 | 107 | 103 | 107 | 97 | 83 | 70 |
| Low °F | 17 | 9 | 17 | 26 | 32 | 38 | 46 | 46 | 38 | 32 | 12 | 13 |
| Precip. (in) | 4.7 | 5.4 | 4.9 | 3.0 | 1.6 | 0.4 | 0.1 | 0.1 | 0.2 | 1.7 | 3.4 | 6.0 |
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 state park
- Day-use fees or passes are common; buy them online before arriving.
- Check park hours: many state parks close at dusk, which affects sunset and night shooting.
- Ask rangers about photography permits for commercial work, models or drones.
- Weekday mornings are the least crowded at popular viewpoints.
- Trail maps often mark overlooks — combine them with the sun azimuth to plan.
- Shoot RAW to keep the most latitude for high-contrast sunrise and sunset scenes.
Season: Spring wildflowers and autumn color are peak seasons in most parks.
Suggested gear: Versatile zoom lens, Tripod, Park pass. Work out exposures with the depth of field, ND filter and NPF rule calculators.
Permits, drones & access
Drones: Drone rules in state parks vary by state and even by park — many require a permit or ban recreational drone flights. Check the park's rules and the FAA B4UFLY app before flying.
Nearby photo spots
Other locations within 40 km of Indian Grinding Rock State Historic Park, closest first.
Cave
Ghost Town
Botanical Garden
Cave
CanyonCanyonCampgrounds nearby (Recreation.gov)
- Oak Knoll Campground27 km (17 mi) · reservable
- Acorn Campground28 km (17 mi) · reservable
- Observation Point Picnic Shelter (Ca)30 km (19 mi) · reservable
- Deer Flat Boat In Campground30 km (19 mi) · reservable
FAQ
When is the best time to photograph Indian Grinding Rock State Historic Park?
What time is golden hour at Indian Grinding Rock State Historic Park?
Where does the sun rise and set at Indian Grinding Rock State Historic Park?
Can you see the Milky Way from Indian Grinding Rock State Historic Park?
Do you need a permit to photograph at Indian Grinding Rock State Historic Park?
How far is Indian Grinding Rock State Historic Park from Sutter Creek?
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.