Know Before You Go
The easiest for groups of people (e.g., families, friends) is to book the visit to the Puerto Princesa Subterranean River through a travel agency, whether in town or in Manila. However, it is also possible to do it yourself. There are public transport going to Sabang and back (though often it's full when going back to Puerto Princesa. Just make sure to pay your entry fee to the Subterranean River in Puerto Princesa. Go early as they have a daily limit.