Hallasan Volcano and Jeju Island

From the air or from the sea approach, Hallasan dominates Jeju Island the way a heartbeat dominates a body — not dramatically, not as a peak one climbs but as a constant, central presence around which everything else organises itself.

The mountain is a shield volcano, meaning its slopes are long and gentle rather than steep, built up by successive lava flows over approximately two million years. Its summit crater contains a lake, Baengnokdam, accessible only on foot — the final hour of the ascent is bare rock and alpine meadow above the tree line.

Hallasan National Park covers most of the mountain. Of the four major hiking routes, the Eorimok Trail on the north face is considered the most scenic: a sustained climb through a forested valley that takes about three and a half hours to the rim of the summit crater.

What strikes experienced hikers is the compression of ecological zones. Within a single day's walk you pass through subtropical broadleaf forest, temperate hardwoods, subalpine conifers, and finally the open alpine zone — a miniature continent's worth of vegetation in a single mountain.

The Geomunoreum Lava Tube System, one of the most significant lava tube cave networks in the world, threads through the island's northern flank. The main system has been closed to the public since 2019 for conservation; smaller nearby tubes remain accessible. The formations inside — stalactites, stalagmites, lava shelves — are considered among the finest of their kind globally.

Jeju's beaches are unlike those of the Korean mainland. Hyeopjae Beach, on the north coast near the Hallasan park entrance, is notable for a dramatic meeting of dark volcanic sand and pale shell sand along its waterline, with clear shallow water that is particularly striking at low tide.

Hallasan is one of the three sacred mountains of Korea, and the mountain and island have long been associated with shamanic traditions. At the base of the mountain are the remains of the Hallasan Fortress, built during the Goryeo period (918–1392), and the Seonbiam Hermitage, founded in 1716, a small retreat whose hillside setting gives views up toward the summit.

UNESCO inscribed Jeju Volcanic Island and Lava Tubes as a World Heritage Site in 2007, recognising the Geomunoreum system as one of the most notable lava tube cave systems globally and the island's accessible volcanic features as making a distinctive and valuable contribution to understanding volcanism worldwide.

The broader island of Jeju rewards extended exploration beyond Hallasan itself. The Jeju Haenyeo — women divers who harvest shellfish, sea urchins and abalone from the seabed without breathing apparatus — are one of the island's most distinctive cultural presences. Though their numbers have declined sharply as the profession has become economically marginal, a small number continue to dive commercially, and their traditions have been inscribed on UNESCO's Intangible Cultural Heritage list. A visit to the Jeju Haenyeo Museum in Jeju City provides essential context for understanding this living tradition. Beyond the volcano and the coast, Jeju's interior is dotted with volcanic cone hills called oreum — many of which have walking trails that offer crater lake views in a more intimate setting than the summit hike. The island's road network circles Hallasan, and the coastal road (the 110-kilometre Jeju Olle Trail) offers some of Korea's most scenic coastal walking, connecting beaches, fishing villages and cultural sites along the shore.

Hallasan at 1,947 m is the highest point in South Korea; climbing it is a multi-hour undertaking accessible to most fitness levels via established trails.

The island's volcanic geology — lava tubes, volcanic cones, crater lakes — is globally significant and inscribed as a UNESCO World Heritage Site in 2007.

Jeju's culture, including the indigenous Haenyeo women divers and the Jeju language, is distinct from mainland Korea, adding cultural depth to the natural landscape.