What is the fine-grained topic of the following text: If you are a hard-core spelunker, Tuguegarao City is your base for the 300-odd mostly unexplored caves in the region — “Caving Adventure Capital of the Philippines” — and if you’re just zooming through like us, Callao Cave is definitely a show cave worth a visit! Only return the topic.
Caving Adventures in Tuguegarao City, Philippines