Granite boulders the size of houses, balanced on white sand: that's the signature of Belitung, a discreet island anchored between Sumatra and Borneo. Ships drop anchor off Tanjung Pandan, the main town, and tenders bring passengers to the pier after a short ride. From the moment you transfer, the sea shows its colours, a gradient of turquoise and green that the dark rocks underline like a brushstroke.

Tanjung Kelayang, gateway to the wonders

About thirty minutes' drive to the north, Kelayang Beach serves as the base camp for the day. The sand is fine, the water crystal clear, and offshore the famous granite boulders form shapes that the imagination delights in naming: one of them recalls a bird's head watching over the bay, the very one that gives the place its name. Brightly coloured fishing boats wait along the shore for the island's most popular outing, the island-hopping tour. Leaning coconut palms, discreet beach huts and the absence of any buildings give the shoreline a look that has stayed true to photographs from thirty years ago. Under the midday sun, the stone takes on pinkish tones that stand out against the dense green of the palms.

From islet to islet

The boats skim along the surface, between reefs and jumbled rocks. Three stops feature on almost every tour:

• Lengkuas, crowned by a 19th-century Dutch lighthouse still in service, whose striped silhouette watches over fish-filled waters perfect for snorkelling;
• Batu Berlayar, a pile of granite that seems to sail along under full canvas at high tide;
• Pasir, a simple sandbar that exists only at low tide, just long enough for a photo with your feet in the water.

Between stops, a mask reveals corals, clownfish and sometimes a passing turtle; the captains know the best anchorages and adapt the route to the day's swell. Bring sandals for walking on the rocks, a dry bag for your camera and a little cash for the refreshments sold on board.

Tanjung Tinggi, a movie set

A little farther east, Tinggi Beach nestles its coves between spectacular heaps of granite, some of them several storeys high. Indonesian cinema made it famous throughout the archipelago after the filming of Laskar Pelangi, adapted from a bestselling novel born on the island, and families pose for photos among the boulders as others would in front of a monument. You can swim in calm, almost warm water before sitting down to grilled fish at one of the huts that line the sand.

Tanjung Pandan, tin and trading houses

On the way back to the pier, the small capital is worth a stroll. Belitung long lived off its tin mines, and the downtown streets still have old-fashioned trading houses, a lively market and simple eateries where coffee is served strong and sweet. The local museum tells the story of the mining era, while the waterfront comes alive at the end of the day, when residents come to watch the boats return. The island can still be visited without crowds, and that tranquillity is part of its appeal.

The boulders in the rear-view mirror

As you head back on board, the rocky silhouettes file past behind the tender's wake, like a discreet farewell. Belitung cultivates neither excess nor artifice: a few beaches shaped with astonishing care, islets within easy reach by boat, a lighthouse counting the years. It's a port call that's simple to describe, and one that makes you want to keep the secret a little longer. In a single day, you'll have seen the essentials; there's just enough left over to justify a return.