If you spend the entirety of your Indonesia vacation above ground, then you're only scratching the surface of the country's beauty — literally. Whether you're you go caving (spelunking) on a regular basis or simply want to take the children on a cool and creepy adventure, caves fit the bill. These caverns may seem foreboding, but they can be surprisingly life-giving, such as Lombok's Bangkang Bat Cave. Others add a new element of excitement to the activities you already know and love, like Bali's Suluban Cave — a favorite haunt of surfers. To enjoy all that Indonesia has to offer, you'll have to dig a little deeper. These Indonesian caves will shed light on the country's original underground scene.