United States Show cave
Great Onyx Cave
14 °C inside, all year.
Dave Bunnell · CC BY-SA 4.0
The descent
The entrance, at 171 m.
The real relief above Great Onyx Cave, 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.
171m
Entrance altitude
from the 30 m relief model
14°C
Inside, all year
the yearly average outside, at the entrance
88m
Rock above
the highest point within 1.5 km
Inside and outside
14 °C inside, all year.
Deep inside, a cave keeps the average temperature of the year outside: about 14 °C here, in January and in August. In August the afternoon reaches 31 °C at the entrance, 17 °C warmer than inside: take a jacket. The best months to escape the heat are from June to September.
- 6°-3°Jan
- 8°-2°Feb
- 14°3°Mar
- 20°8°Apr
- 24°14°May
- 29°19°Jun
- 31°21°Jul
- 31°20°Aug
- 28°16°Sep
- 21°9°Oct
- 14°2°Nov
- 8°-1°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 Kentucky, US
Great Onyx Cave is a show cave in United States. The entrance is at 171 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.
- Cave Citynearest town · 14 km in a straight line
- Viewpointsnearest viewpoint · 3.6 km from the entrance
- Louisville Muhammad Ali International Airport (SDF)nearest airport with scheduled flights · 110 km in a straight lineCar hire at SDF airport (Louisville)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.
- 5other cave entrances within 3 kmSalts, Crystal Cave, Great Onyx Cave and 2 more
- 1viewpoints within 3 km
- 1marked hiking routes within 3 kmGreen River Bluffs Trail
- 5campsites within 8 kmMaple Springs Group Campground, Turnhole Bend CG, Homestead Campsite and 2 more
- 3hotels and guesthouses within 8 kmThe Wayfarer B&B, Hickory Cabins, Mammoth Cave Lodge
- springs within 2 km
- sinkholes within 3 km
- caving clubs and spots within 15 km
- climbing crags within 3 km
- named waterfalls within 4 km
- car parks within 2 km
- information boards and visitor centres within 3 km
- bus stops within 2 km
- restaurants and cafés within 3 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
- Cave City14 km in a straight line
- Horse Cave16 km in a straight line
- Brownsville17 km in a straight line
- Munfordville18 km in a straight line
Month by month
The weather outside, at the entrance.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Afternoon | 6 | 8 | 14 | 20 | 24 | 29 | 31 | 31 | 28 | 21 | 14 | 8 |
| Afternoon | 6 | 8 | 14 | 20 | 24 | 29 | 31 | 31 | 28 | 21 | 14 | 8 |
| Night | -3 | -2 | 3 | 8 | 14 | 19 | 21 | 20 | 16 | 9 | 2 | -1 |
| Rain (mm) | 100 | 120 | 116 | 139 | 142 | 119 | 140 | 108 | 98 | 108 | 105 | 128 |
| Rainy days | 11 | 10 | 12 | 12 | 14 | 15 | 16 | 13 | 10 | 9 | 9 | 12 |
| Sun hours/day | 3.6 | 4.0 | 5.1 | 6.9 | 7.3 | 8.8 | 8.4 | 8.0 | 7.2 | 6.0 | 4.9 | 3.3 |
| Snow on the ground (cm) | 10 | 9 | 3 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 2 | 7 |
| Afternoon | Afternoon | Night | Rain (mm) | Sun hours/day | |
|---|---|---|---|---|---|
| Jan | 6 | 6 | -3 | 100 | 3.6 |
| Feb | 8 | 8 | -2 | 120 | 4.0 |
| Mar | 14 | 14 | 3 | 116 | 5.1 |
| Apr | 20 | 20 | 8 | 139 | 6.9 |
| May | 24 | 24 | 14 | 142 | 7.3 |
| Jun | 29 | 29 | 19 | 119 | 8.8 |
| Jul | 31 | 31 | 21 | 140 | 8.4 |
| Aug | 31 | 31 | 20 | 108 | 8.0 |
| Sep | 28 | 28 | 16 | 98 | 7.2 |
| Oct | 21 | 21 | 9 | 108 | 6.0 |
| Nov | 14 | 14 | 2 | 105 | 4.9 |
| Dec | 8 | 8 | -1 | 128 | 3.3 |
Averages 1991–2020 (NASA POWER) for a cell about 55 km wide, brought to the altitude of the entrance (171 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 | 143% | 150% | 198% | 84% | 75% | 130% | 100% | 128% | 99% | 136% | 49% | 74% |
| 2021 | 114% | 138% | 140% | 50% | 87% | 97% | 88% | 140% | 101% | 102% | 56% | 94% |
| 2022 | 139% | 159% | 77% | 91% | 63% | 59% | 168% | 88% | 58% | 38% | 73% | 86% |
| 2023 | 149% | 81% | 125% | 55% | 72% | 98% | 88% | 95% | 52% | 48% | 42% | 47% |
| 2024 | 157% | 86% | 60% | 89% | 191% | 71% | 122% | 36% | 161% | 11% | 107% | 116% |
| 2025 | 113% | 189% | 128% | 201% | 132% | 131% | 60% | 29% | 96% | 113% | 62% | 49% |
130% or more: wet month 70% or less: dry month
Caves nearby.
Great Onyx Cave
United States
- —Depth
- —Galleries
- 171 mEntrance altitude
- 14 °CInside, all year
Mammoth Cave
United States · 4 km
- —Depth
- 644 kmGalleries
- 235 mEntrance altitude
- 14 °CInside, all year
Horse Cave
United States · 16 km
- —Depth
- —Galleries
- 193 mEntrance altitude
- 14 °CInside, all year
Colossal Cavern
United States · 3 km
- —Depth
- —Galleries
- 213 mEntrance altitude
- 14 °CInside, all year
Where these figures come from
| Name, type, published depth and length, visitors | Wikidata (Q5599714) · 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 |
Every figure is an average, an estimate or a count from a public dataset. Licences and methods: data sources.
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