What a great day. We drove a fair few miles deep into karst territory, up hill, down dale, along windy roads with bamboo towering over us, rain forest vegetation on both sides and pot holes beneath us. Our first stop was Cueva Clara in the Parque Las Cavernales Rio Camuy. This cave system is home to not only 13 species of bats but also the world's 3rd largest subterranean river and a cavern 22m long by 65m high which has a wonderful array of stalagmites and stalactites. From the cave we drove on to the Arecibo Observatory for our own James Bond experience (remember the dome from Goldeneye?) and a tour. The telescope may not be the largest in the world anymore but it is still the most powerful. Awesome technology.