As the plane flies above the Indian Ocean, I see land come into view: layers of forest fringed by beach tantalisingly stretched out under the midday sun. We are around 100km off the west coast of Sumatra, approaching the island of Nias. Tourists gape at the view below through the windows of the plane, which a moment later will land in Gunungsitoli.

At Gunungsitoli’s Binaka airport, a noticeable number of surfboards are brought out from the hull of the aeroplane along with the suitcases and backpacks. Nias first came to the attention of international surfers in 1975, when three Australians travelled to the southern part of the island and were overjoyed to discover some of the best, most consistent waves to be found anywhere in the world. Since the 1980s, the island has become a renowned surfing destination for visitors from many countries. However, it is not only the fabulous beaches and stellar surfing that make Nias remarkable – it is also known for its Stone Age relics, unique culture and legendary warriors.

Along with my guide Dermawan Buaya, often called Feber, I cross the small streets to approach the hills at the edge of Gunungsitoli. On a hill with a winding incline, I meet Ama Silvi, a man whose grin reveals red gums from chewing betel nut, the custom of many adult men in the villages of Nias.

Asu Island is on the western point of Nias, facing out to the Indian Ocean.

“Behind my house is the home of our Stone Age ancestors,” says Ama, smiling. He takes me down a narrow street behind his house leading to his ancestral home: a damp cave, a refreshing place to take shelter from the blazing noon sun. The mouth of the cave opens towards the coast, where the city of Gunungsitoli has grown since it was shaken by earthquakes in 2004 and 2005, the tightly packed houses stretching out to the blue sea beyond.

Together with Feber and Ama, I sit at the mouth of this ancient place, called Tögindrawa Cave, which was excavated in 1999 by the Nias Heritage Museum in collaboration with Airlangga University. What they found was remarkable: evidence of life which proved that this cave was occupied more than 12,000 years ago.

As we sit there, a group of children chase each other nearby, while birds dart past above, their tweets tracing the echoes of voices. Stalactites dangle like a lace net. There is a profound sense of tranquillity here, as if to remind us that the ancestors of the Nias people lived calmly in this peaceful stone cave so many millennia ago.

After relaxing at Tögindrawa, Ama takes me to his house to meet his wife and children, and to tell stories of ancient deserted caves on the edge of the forest behind his house.

From here, Feber and I slip away to the traditional settlements in Tumori village, which are also very quiet. Feber explains that the villages often seem deserted in the middle of the day, as most people are either in the fields or having a siesta. With Feber at the wheel, we venture on to Onowaembo waterfall, a refreshing diversion on a hot afternoon.

Pantai Sorake is a favourite spot of international surfers.

We then return from the high ground to the heart of Gunungsitoli City. Under the shady trees of Miga Beach, I strike up a conversation with 60-year-old Agus Mendröfa, who greets me with coffee and smoky fried bananas. With a surge of enthusiasm, he talks about the fascinatingly long history of the island’s culture, which some archaeologists believe is one of the only remaining Megalithic cultures to have survived through the ages. “Nias is now better known as a surfing destination. However, the people of Nias have lived here since the Stone Age. This is proven by the stone relics and artefacts that are still protected on this island. If one only visits Gunungsitoli it is not enough. If you don’t go to southern Nias as well, why bother with Nias at all?” Agus muses.

With Agus’s words still in my head, the next day, I am joined by another local guide, Boifaroi Sarumaha, who takes me on a winding road towards the south. In Gomo subdistrict, modern settlements and villages are situated on piles of Megalithic rocks and ancient remains. Following narrow roads on the edge of green cliffs, I arrive at a small village of wooden houses. Old men sit sipping coffee, children run around, and women dry their field produce in the yards of their homes, sharing the space with almost blackened Megalithic rocks. According to local legend, the Gomo area is the original land of the Nias people and is considered a spiritual and cultural centre for the Nias community.

The western coast of Nias Island offers more incredible waves. There’s good surfing all year around.

Around 60km from Gomo, I visit a traditional village called Bawömataluo. The village, which is described in records dating back to the 19th century, is located at a height of 270m and is crammed with more than 100 traditional houses. Since ancient times, Bawömataluo has been well known for its courageous warriors; a traditional test of their skill is a ritual called fahombo or hombobatu, which involves jumping over rocks more than two metres tall in the middle of the village. The residents also maintain their links to the past by continuing to perform customary war dances, a popular spectacle among visitors. The village has been placed on the tentative list of UNESCO World Heritage Sites and, in 2012, was identified as one of the Wonders of the World from Indonesia by the Real Wonder of the World Foundation.

We leave Bawömataluo as the sun heads to the west, the waves of the vast ocean stretching out before us, surfers dotted among them. I ponder alone at the village gate, between the black rocks of the past, considering the island of the present and how it has come so far from the ancestral times of the Megalithic era.