Brazil has at least 3,000 caves officially identified – and some of them are absolutely phenomenal. You will find here a selection of images found at Flickr. You should also visit Fotografia magazine’s website to check 20 years of underground photos by Alexandre Lobo.
In case you are wondering, the best source online of information about these geological formations is the Sociedade Brasileira de Espeleologia website (unfortunately, most of it only in Portuguese).
One of the divine experiences of traveling along the Brazilian lands is the surprise appearance of little waterfalls along the road. You stop the car, dive into the shower, fill your bottle and go back to the car, dripping, in bliss.