Hormuz Island Colours

Hormuz Island, 8 km off Bandar Abbas in the Strait of Hormuz, is a salt dome whose rocks come in red, ochre, yellow, purple, grey and white, which is why it is called the “rainbow island”. Its best-known landscape is Rainbow Valley (دره رنگین‌کمان), where these colours lie side by side in small hills, and the island’s red earth, called golak, even stains its beaches and waves.

Why the island is so colourful

More than 500 million years ago, at the end of the Precambrian, shallow seas over what is now the Persian Gulf evaporated again and again, leaving thick beds of salt and gypsum. Volcanoes erupted at the same time, and iron-rich sediments and volcanic rocks were laid down between the salt layers. Geologists call this mixed package the Hormuz Series.

Later, kilometres of younger sediment buried it. Salt is lighter than the rock above it and flows slowly under pressure, like very stiff toothpaste. Over millions of years it pushed upwards in columns called diapirs, or salt domes, and in places broke through to the surface. Hormuz is one of these: from space it appears as a roughly round island with concentric rings of rock, the core of a salt column that has risen out of the sea.

As the salt rose it carried fragments of the other Hormuz Series rocks with it, torn up and jumbled. Rain is scarce here, so salt that would dissolve in a wetter climate survives at the surface, and erosion exposes all the pieces at once. The colours come from different minerals:

• Red and purple: iron oxides, above all hematite, the source of golak.
• Ochre and yellow: other iron minerals and weathered, sulphur-bearing rock.
• White and pink: rock salt and gypsum.
• Grey, green and black: volcanic rocks and shales from the old seafloor.

That is why colours change over a few metres: you are walking across fragments from very different rocks that the salt brought up together.

The sites

Rainbow Valley

A small area of low hills and gullies inland, where red, ochre, yellow and grey soils lie in bands and patches. It is the place most photographs of Hormuz are taken. Walk the gullies in the early morning or late afternoon, when the colours are richest and the heat bearable.

Red Beach

On the coast, iron-rich earth washes from the cliffs into the sea and turns the sand and the breaking waves red. Look at the sand closely and you may see it sparkle with tiny mineral flakes.

Valley of Statues and Silence Valley

Wind and salt weathering have carved the soft rock into shapes, and visitors find faces, animals and figures in them. Silence Valley, inland, is a quieter maze of eroded salt and clay hills.

Salt Mountain and salt cave

Where the salt itself reaches the surface it forms white and pinkish walls. A cave in the salt, sometimes called the cave of the Salt Goddess, has glittering salt walls and crystals.

Golak: the edible earth

Hormuz islanders use golak as a pigment and in cooking, including a well-known local sauce served with bread, and artists in recent years have used the island’s soils for painting and sculpture. Our Hormuz Island page describes this local culture, along with the history of the medieval kingdom of Hormuz and its Portuguese fort.

The colours are not endless. Heavy extraction of ochre for trade has damaged parts of the island, and Iran’s Department of Environment has acted to protect it. Do not take soil or rocks away, and avoid driving off tracks, which scars the soft hills for years.

Practical notes

• Hormuz is reached by passenger boat from Bandar Abbas; check current schedules locally.
• A ring road circles the island. Local drivers offer tours by tuk-tuk or car; cycling is possible in the cool season.
• Come between November and March. Summer heat and humidity are severe, and there is little shade in the valleys.
• Carry water and a hat, and wear shoes that can get stained red.
• Dress modestly in the village, ask before photographing people, and follow your own government’s travel advice for Iran.

Hormuz is often combined with Qeshm Geopark, whose Namakdan salt dome belongs to the same family of salt domes, and with a stay in Bandar Abbas. The Safavid capture of the island from the Portuguese is told on The capture of Hormuz (1622).