PEÑABLANCA, Cagayan, Philippines -- Despite its searing hot weather, Cagayan province is home to some of the coolest adventure destinations in the country.

With over 300 known caves (97 of which have been documented while only 37 have been explored in the past three decades) and countless river systems, this northern province is a must-go-to place for adventure and travel junkies.

Tucked away in the mountains of the unassuming town of Peñablanca, a 30-minute drive from Cagayan’s capital Tuguegarao City, is Callao Cave, one of the province’s most popular.

The cave was named after the Kallaw bird, which used to thrive in the area, but whose numbers have dwindled due to hunting.

Visitors need to climb up 187 steps up the side of the mountain before reaching the entrance of Callao Cave, but it the majestic limestone formations make it worth the effort.

A viewing deck is set up halfway up where tourists can rest and enjoy a picturesque view of the Pinacanauan River below.

Callao Cave’s seven chambers are filled with centuries old stalactites and stalagmites and it also features several magnificent domes and skylights.

The first chamber of Callao Cave known as the “Aviary Room” is home to several species of birds. In a corner right at the entrance of the first chamber is a cordoned-off site where archaeologists from the University of the Philippines discovered human remains and ancient tools dating back to the Neolithic era.

The second chamber, which is the main attraction of the “Callao Cave,” is the Divine Room which the locals have turned into a cathedral due to the natural formation of grottos on the wall and a 160-foot high natural skylight.

Wedding ceremonies can be held in the chapel but locals say that the groom must carry the bride all the way up the 187 steps into the Callao cave before the ceremony.

After the Divine Area is the “Dark Room,” which is named so because it is pitch black inside. Caretakers use incandescent bulbs to guide visitors.

Known as the “Cream Room, the fourth chamber features a large rock formation which looks like three scoops of ice-cream. On the other side of this chamber are the “Three Kings” and the “Elephant Mother and Child” formations while on the side of the ceiling are the “Wings of an Angel” and “Head of St. Joseph” formations.

The next chamber is called the “Jungle Area” since it is home to several animal-shaped rock formations like the “Hornbill,” “Maya,” “Giant Turtle,” and a rock shaped like monkey’s head hence the name “King Kong.”

The sixth room is called the “Adventurous Area” since it features another cave within the chamber. However, adventure-seekers need to make use of another entrance on the other side of the mountain to be able to access the second cave situated halfway up the ceiling.

Lastly, the seventh and last chamber of the Callao Cave is called the “Sun Room”. If tourists come early in the morning preferably between 8 a.m. to 10 a.m., they will be treated to a spectacular view of the chamber as sunrays peek through a sky light on the wall.

When touring the Callao Cave for the first time, it’s advisable to request for a guide. Not only are they helpful for pointing the various limestone formations within the various chambers, they will also tell you which paths to take since muddy areas can be slippery.

Visitors are asked not to litter within the park’s premises and vandalism is strictly prohibited.