Mount Teide

At sunset the summit throws its shadow across the sea: a clean triangle more than 40 km long that reaches Gran Canaria in the evening and La Gomera at dawn. The mountain itself has no such neat outline. The perfect triangle is a trick of perspective.

At the top the air goes quiet, and the small summit cone, El Pitón, is still alive, with fumaroles in its crater giving off sulphur gases. Below, the Las Cañadas caldera spreads out as a plain of lava at around 2,000 m, and Pico Viejo's crater, 800 m across, opens on the western flank. In May and June the Teide bugloss puts up red flower spikes up to 3 m tall, higher than a person standing beside them. After dark the sky is clear and steady enough that an astronomical observatory works on the slopes.

• Summit permit: the last 200 m to the top need a free permit, arranged before you go.
• The air at the upper cable car station is thin and can bring on dizziness, more so with heart or lung conditions.
• Temperatures swing about 15 °C over a day and winter brings snow; pack warm layers even when the coast is hot.
• The UV index at altitude passes 11 in midsummer, so cover up and use sun cream.
• There is no drinking water near the summit; carry your own.

A single public road crosses the Las Cañadas caldera from north-east to south-west, climbing through pine forest before the trees give out and the lava fields begin. The lower cable car station stands beside that road at 2,356 m, with car parks and the Teleférico del Teide bus stop next to it, about 2.5 km in a straight line from the summit. The cabin takes eight minutes to reach the upper station at 3,555 m. From there a footpath continues to the top, and the final 200 m are open only to permit holders. Several footpaths also climb from below to the upper station, for those who want to walk the whole way.

Best: late afternoon to sunset on a clear day, and May to June for the flowers. The setting sun throws Teide's shadow across the sea towards Gran Canaria, and the Teide bugloss blooms in the caldera in late spring.

Avoid: winter if you plan to walk to the summit without crampons and poles, and the middle of the day in high summer. Snow and ice lie on the upper path in winter, and the UV index at this altitude passes 11 in midsummer.

Teide and the whole Las Cañadas caldera lie inside Teide National Park, a UNESCO World Heritage Site. The final 200 m to the summit are restricted: climbing them requires a free permit, and without one the path to the top is closed to you. Keep to the marked footpaths across the park and leave rocks and plants where they are; many of the plants on these slopes grow only on Tenerife.