We left Karumba and arrived at Mount Surprise after a long day driving. When we got there we set up and went for a swim in the pool while dad went for a walk to the river. All the trees were filled with hundreds of butterflies. The next day we woke up and drove to the Undara lava tubes. When we got there we went on a tour through the dark tubes. I thought they were amazing. They were made over 190,000 years ago and they are the longest lava tubes in the world, stretching over 160 kilometres. The tour guide said that at some times of year if you go to deep in the cave you will suffocate because of the high amount of carbon dioxide. In one of the caves we saw tiny bats. In another cave we got to the end of the tube and turned all the torches off and it was pitch black.