If you are interested in exploring caves for your proposal and/or celebration, you might want to join the National Speleological Society.
And here are a few caving destinations that pack a whole lot of wow:
- Waitomo Glowworm Caves, New Zealand
- Cosmic Cavern, Arkansas
- Mystery Cave, Minnesota
- Mammoth Cave, Kentucky
- Puerto-Princesa Underground River, Palawan, Philippines
- Barton Creek Cave
- Phong Nha Cave, Phong Nha Ke Bang National Park, Vietnam
If you have more great caving suggestions, please leave them in the comments below. Many thanks!