Geography of La Gomera

La Gomera is one of the smallest islands in the Canary archipelago: 370 square kilometres of surface, 97 kilometres of coastline and 333 kilometres from the African mainland. It is also one of the oldest: geologists estimate its age at around 12 million years, the fifth in the archipelago's order of formation. Its most singular trait is the absence of recent volcanism: on La Gomera, as on Fuerteventura and Gran Canaria, no eruptions are known in the last 500 years, and not only does it lack historical eruptions, it barely preserves one or two well-formed volcanic cones. This prolonged eruptive calm gives it a landscape totally different from the rest of the islands, shaped by erosion rather than by fresh lava.

That long geological history is visible on the surface. All along the arc surrounding the town of Vallehermoso the Basal Complex can be observed — the submerged base on which the islands grew, exhumed here by erosive agents. Elsewhere fossil volcanoes emerge, ancient cones reheated and buried by later lava flows. Erosion has dismantled the soft volcanic edifices and laid bare their more resistant chimneys: this explains the famous Gomeran roques. The Los Roques Natural Monument groups together Agando —an enormous outcrop 1,250 metres high—, Ojila, La Zarcita and Carmona, while on the north coast the Los Órganos rock, a salic plug with spectacular columnar jointing, forms a cliff of vertical pipes resembling an organ that can only be admired from the sea.

The heart of the island is a central plateau crowned by Alto de Garajonay, which at 1,487 metres is the island's highest point. On these summits Garajonay National Park was created in 1981, covering 3,984 hectares, roughly 10% of the island's surface. It is an eminently botanical park: it holds the finest remaining expression of laurisilva in the archipelago, an evergreen forest considered a living fossil of the subtropical woodlands that grew on the shores of the Mediterranean in the Tertiary. La Gomera's laurel forest concentrates nearly half of the extent of this type of woodland in all the Canaries and, in recognition of that exceptional value, the park was declared a World Heritage Site by UNESCO in 1986, barely five years after its creation.

The forest exists thanks to the trade winds and the sea of clouds. The trade winds blow steadily for much of the year, especially in summer, and form over the island's summits a layer of mist of variable thickness that sits directly upon them. Condensing on the vegetation, that mist gives rise to so-called "horizontal rain", an atypical precipitation contributing some 125 litres per square metre a year in the national park area. The lack of greater altitudes, on the other hand, prevents the development of natural pine forests. The moisture of the summits also feeds a hydrological rarity: in the El Cedro ravine runs one of the only two permanent streams in the Canaries, without ever becoming a river.

La Gomera is, without doubt, the most representative island for studying ravines. They are arranged radially: they set out from the central core and descend towards every coast. The virtual absence of recent volcanic activity and the great quantity of runoff water have been carving the terrain for millions of years, leaving only the most resistant materials exposed. The deep excavation of some ravine heads, such as that of Valle Gran Rey, even suggests that past climatic conditions were much wetter, with more abundant flows. Valle Gran Rey, Vallehermoso, Hermigua and Benchijigua are some of these deep valleys, separated by ridges and interfluves that fragment the island into districts isolated from one another: 78.8% of the island's terrain has slopes steeper than 30%.

The coast shares the same abrupt character. La Gomera's shoreline lacks inlets suitable for harbours and its beaches are wedged between cliffs. There are no coastal roads: the main routes cross the interior of the island, and in local speech "costa" and "monte" name the territory's two great bands, the shoreline with its adjacent lands and the high central zone. The capital, San Sebastián de La Gomera, sits on the sediments of a ravine mouth, one of the few places where the relief grants flat ground beside the sea; in the north-west, Valle Gran Rey displays its blend of palm groves and districts of white houses, and in the north stands the hamlet of Agulo below the crag of the Abrante viewpoint.

The human geography is a direct child of this relief. To farm the slopes, the Gomerans terraced the land with stone walls built by hand: these are the bancales, visible in Valle Gran Rey and across the island, although many now lie abandoned and exposed to erosion. The palm groves of Valle Gran Rey, Tazo and Vallehermoso rank among the most famous in the Canaries. Settlement is scattered by altitude bands: the coastal valleys concentrate the population, the middle stretches between 200 and 500 metres alternate small hamlets and cultivated land, and on the leeward side villages grew between 800 and 1,200 metres, such as Arure, Chipude, El Cercado and Igualero, while on the windward side there are no villages above 750 metres. In a territory this fragmented, where many areas were reachable only by footpaths, the Silbo Gomero arose as a brilliant cultural response: a whistled language able to travel from ravine to ravine where the voice cannot reach.