United States Show cave
Crystal Grottoes
12 °C inside, all year.
Mdnghtshdw · CC BY-SA 3.0
The descent
The entrance, at 146 m.
The real relief above Crystal Grottoes, measured on the Copernicus model every 30 m, and the cave going down at the same vertical scale.
The depth is the one published by those who explored it; the shape of the galleries is a sketch, not a survey. No depth has been published for this cave yet.
146m
Entrance altitude
from the 30 m relief model
12°C
Inside, all year
the yearly average outside, at the entrance
31m
Rock above
the highest point within 1.5 km
Inside and outside
12 °C inside, all year.
Deep inside, a cave keeps the average temperature of the year outside: about 12 °C here, in January and in August. In July the afternoon reaches 31 °C at the entrance, 19 °C warmer than inside: take a jacket. The best months to escape the heat are from June to August.
- 3°-6°Jan
- 5°-5°Feb
- 10°-1°Mar
- 18°5°Apr
- 23°12°May
- 28°17°Jun
- 31°19°Jul
- 30°19°Aug
- 26°14°Sep
- 19°7°Oct
- 12°1°Nov
- 5°-3°Dec
Outside: afternoon and night averages for 1991–2020 (NASA POWER) brought to the altitude of the entrance. Inside: the yearly average, which deep parts of a cave keep. Near the entrance it follows the weather a little.
Cave in Maryland, United States
Crystal Grottoes is a show cave in United States. The entrance is at 146 m. It has stalactites and stalagmites. It is open to visitors.
Getting there.
- Show cave: open to visitorsUsually with a guided tour; check times and tickets on the official site.
- Boonsboronearest town · 2.3 km in a straight line
- Parking 1,500 m awaynearest car park in OpenStreetMap, straight line
- Hagerstown Regional Richard A Henson Field (HGR)nearest airport with scheduled flights · 24 km in a straight lineCar hire at IAD airport (Dulles)Discover Cars · sponsored link↗
Plan the visit
Guided tours, a bed nearby, a car.
Some links above are affiliate links: if you book through them we may earn a commission, at no extra cost to you. It never changes what the data on this page says.
From above.
The ground above the cave, with the relief shaded, the line of the section and what people have mapped around the entrance.
N
1.5 km
Sentinel-2 cloudless 2016 (EOX, CC BY 4.0), 6.0 × 6.0 km, north up. The line is the section above. Points © OpenStreetMap contributors.
Around the entrance.
- 1other cave entrances within 3 kmCrystal Grottoes Caverns
- 11car parks within 2 km
- 19campsites within 8 kmAnnapolis Rock AT Camping Area, Greenbrier State Park - Dogwood Campground, Greenbrier State Park - Cedar Campground and 16 more
- 1hotels and guesthouses within 8 kmInn Boonsboro
- 2restaurants and cafés within 3 km
- springs within 2 km
- sinkholes within 3 km
- caving clubs and spots within 15 km
- viewpoints within 3 km
- marked hiking routes within 3 km
- climbing crags within 3 km
- named waterfalls within 4 km
- information boards and visitor centres within 3 km
- bus stops within 2 km
Counted in OpenStreetMap, the map anyone can edit, around the entrance. A low number may just mean nobody has mapped it yet. © OpenStreetMap contributors (ODbL).
Towns nearby
- Boonsboro2.3 km in a straight line
- Keedysville2.3 km in a straight line
- Myersville9.5 km in a straight line
- Saint James10 km in a straight line
- Middletown13 km in a straight line
- Shepherdstown13 km in a straight line
- Halfway15 km in a straight line
- Robinwood16 km in a straight line
In our other atlases
What else is around Crystal Grottoes.
The river at the entrance, the waterfalls, the lakes, the mountains and volcanoes above, the canyons, beaches and islands nearby — from our other atlases.
Peakyas10 mountains within 10 kmFigures from the sister sites' databases (Wikidata, HydroATLAS, GeoNames, NOAA, OpenStreetMap). Links open when each site is online.
Month by month
The weather outside, at the entrance.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Afternoon | 3 | 5 | 10 | 18 | 23 | 28 | 31 | 30 | 26 | 19 | 12 | 5 |
| Afternoon | 3 | 5 | 10 | 18 | 23 | 28 | 31 | 30 | 26 | 19 | 12 | 5 |
| Night | -6 | -5 | -1 | 5 | 12 | 17 | 19 | 19 | 14 | 7 | 1 | -3 |
| Rain (mm) | 69 | 68 | 83 | 94 | 117 | 112 | 107 | 94 | 112 | 101 | 77 | 90 |
| Rainy days | 9 | 9 | 10 | 11 | 14 | 14 | 15 | 13 | 10 | 8 | 8 | 9 |
| Sun hours/day | 3.8 | 4.9 | 5.4 | 6.6 | 6.9 | 8.1 | 8.3 | 7.4 | 6.4 | 5.3 | 4.6 | 3.5 |
| Snow on the ground (cm) | 14 | 14 | 7 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 3 | 12 |
| Afternoon | Afternoon | Night | Rain (mm) | Sun hours/day | |
|---|---|---|---|---|---|
| Jan | 3 | 3 | -6 | 69 | 3.8 |
| Feb | 5 | 5 | -5 | 68 | 4.9 |
| Mar | 10 | 10 | -1 | 83 | 5.4 |
| Apr | 18 | 18 | 5 | 94 | 6.6 |
| May | 23 | 23 | 12 | 117 | 6.9 |
| Jun | 28 | 28 | 17 | 112 | 8.1 |
| Jul | 31 | 31 | 19 | 107 | 8.3 |
| Aug | 30 | 30 | 19 | 94 | 7.4 |
| Sep | 26 | 26 | 14 | 112 | 6.4 |
| Oct | 19 | 19 | 7 | 101 | 5.3 |
| Nov | 12 | 12 | 1 | 77 | 4.6 |
| Dec | 5 | 5 | -3 | 90 | 3.5 |
Averages 1991–2020 (NASA POWER) for a cell about 55 km wide, brought to the altitude of the entrance (146 m) with the standard lapse rate. Not a forecast.
Photographs
Inside and around.
Recent years
Wet years, dry years.
Rain of each month as a share of the 1991–2020 average. A dry year means a lower river and hotter rock; a wet one, more water in the gorge.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 2020 | 115% | 94% | 91% | 140% | 43% | 78% | 63% | 143% | 58% | 117% | 184% | 124% |
| 2021 | 65% | 141% | 73% | 61% | 70% | 82% | 75% | 130% | 175% | 73% | 38% | 26% |
| 2022 | 94% | 89% | 65% | 73% | 136% | 65% | 87% | 83% | 89% | 65% | 104% | 126% |
| 2023 | 66% | 72% | 73% | 95% | 22% | 60% | 85% | 71% | 110% | 38% | 81% | 149% |
| 2024 | 217% | 91% | 127% | 104% | 84% | 67% | 66% | 194% | 82% | 11% | 58% | 89% |
| 2025 | 51% | 77% | 51% | 65% | 196% | 105% | 113% | 33% | 50% | 63% | 45% | 46% |
130% or more: wet month 70% or less: dry month
Caves nearby.
Crystal Grottoes
United States
- —Depth
- —Galleries
- 146 mEntrance altitude
- 12 °CInside, all year
Skyline Caverns
United States · 81 km
- —Depth
- —Galleries
- 187 mEntrance altitude
- 13 °CInside, all year
Luray Caverns
United States · 116 km
- —Depth
- —Galleries
- 297 mEntrance altitude
- 13 °CInside, all year
Indian Echo Caverns
United States · 117 km
- —Depth
- —Galleries
- 116 mEntrance altitude
- 11 °CInside, all year
Where these figures come from
| Name, type, published depth and length, visitors | Wikidata (Q5191205) · CC0 |
|---|---|
| The relief above, the entrance altitude, the section and the 3D model | Copernicus DEM GLO-30 · © DLR e.V., © Airbus Defence and Space GmbH, Copernicus/ESA |
| Climate | NASA POWER, 1991–2020 |
| Entrances, springs, sinkholes, opening hours and what is around | © OpenStreetMap contributors · ODbL |
| Images | EOX Sentinel-2 cloudless 2016 · CC BY 4.0; Wikimedia Commons |
| Rivers, waterfalls, lakes, mountains, canyons, beaches and islands nearby | Coastya, Lakeyas, Peakyas, Cascadyas, Islandyas, Riveryas |
Every figure is an average, an estimate or a count from a public dataset. Licences and methods: data sources.
The family
Do you prefer beaches, lakes, mountains, waterfalls, islands, rivers, canyons, caves, dark skies, viewpoints, birdwatching or forests?
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