The voyage that reached the Americas in 1492 did not sail from Spain to the New World in one go. It sailed from Andalusia to the Canary Islands, spent nearly a month here having a broken rudder fixed and a set of sails recut, and only then set off west — from San Sebastián de La Gomera on 6 September. Every one of Columbus's four crossings began the same way, and so did most of the Spanish Atlantic traffic for the next three hundred years.

The reason is wind. A sailing ship leaving Europe at the latitude of Lisbon meets variable headwinds; drop south to the Canaries and you pick up the north-east trade wind, which blows steadily west across the Atlantic at that latitude and will carry you to the Caribbean without asking much of you at all. Columbus had sailed these waters before, knew the pattern, and used it. Our page on the Canary Current and the trade winds explains the mechanism the whole age of sail hung on.

So the islands were not a scenic diversion. They were the last provisioning stop, the last shipyard, the last place to take on water and firewood and cheese before three thousand miles of open ocean — and for a century and a half they were the only Atlantic islands in Castilian hands that could do the job.

August 1492: the rudder breaks

The little fleet — the Santa María, the Pinta and the Niña — left Palos de la Frontera on 3 August and was in Canarian waters within a week. Almost immediately the Pinta's rudder came adrift, possibly through sabotage by a crew with no appetite for the voyage; Columbus suspected exactly that in his journal. The damage was serious enough to need a proper yard.

What followed was a month of maritime housekeeping. The Pinta was repaired at Las Palmas de Gran Canaria, and the Niña had her triangular lateen rig converted to square sails — a change that looks technical and was decisive, because square sails run far better before a following trade wind than lateens do. Columbus himself went back and forth between Gran Canaria and La Gomera while the work went on, and the fleet reprovisioned with water, wood, salt meat, cheese and, by tradition, a quantity of the islands' own produce.

Beatriz de Bobadilla

The person he went to see on La Gomera has generated five centuries of speculation. Beatriz de Bobadilla y Ossorio had been a beauty at the Castilian court, was sent away from it — the standard story is that Queen Isabella wanted her at a safe distance from King Ferdinand — and married Hernán Peraza the Younger, the lord of La Gomera. Peraza was killed in 1488 during a Gomeran uprising provoked, in part, by his own conduct, and the reprisals that followed were savage. Beatriz was left governing the island from the Torre del Conde, the squat stone keep that still stands in a park in the middle of San Sebastián.

Whether she and Columbus were lovers is unprovable. What is on record is that he called at her island on the way out, stayed longer than the repairs strictly required, and returned on the second voyage in 1493 as well. Contemporaries gossiped about it at the time. It is one of those historical questions where the evidence is thin and the story is too good to die.

The water that baptised America

Here is the detail worth carrying away, and you can put your hand on it. In San Sebastián de La Gomera, in the courtyard of the old customs house on Calle Real, there is a well. The fleet drew water there before the final departure, and an inscription on the wall records the claim that with this water America was baptised. It is a small, plain, beautifully unshowy monument — a stone wellhead in a shaded yard, usually with nobody looking at it — and it may be the single most consequential bucket of water in European history.

The same street has the house Columbus is said to have lodged in, and the church of the Asunción nearby claims the mass the crews heard before sailing. Local tradition is generous about all of it. The well is the one that convinces.

San Sebastián markets itself as the Isla Colombina, the Columbus island, and the sights are within ten minutes' walk of the ferry ramp — which makes them very easy to fit into a day trip across from Tenerife, though the island deserves longer than that.

The Casa de Colón in Las Palmas

Gran Canaria's contribution is a handsome one. In the old quarter of Vegueta stands the former residence of the island's governors, where Columbus is traditionally said to have stayed while the Pinta was being repaired. The building is now the Casa de Colón, a museum of the voyages, the Atlantic crossing and the islands' role in it, arranged around courtyards with carved wooden balconies and kept cool by stone. Historians are cautious about whether he actually slept there; the house is worth an hour regardless, and the reconstruction of a ship's cabin below decks does more to explain what those crossings were like than any amount of text.

Did he see Teide erupt?

The journal records the crews seeing fire coming from a great mountain on Tenerife as they passed — an island still unconquered at the time, and one that seems to have alarmed the sailors considerably. Whether that was a genuine eruption on Teide, activity elsewhere on the volcano, or something mundane misread by frightened men is argued over. The fact that the question is live at all tells you how new and strange these islands still were to Europeans in 1492: the conquest of the last unconquered islands was not finished until 1496, four years after the first crossing.

Every voyage after that

The second expedition in 1493 — seventeen ships, over a thousand men, and a cargo list intended to found a colony — stopped at Gran Canaria and La Gomera and loaded livestock, seeds and cuttings. This is where the islands stop being a filling station and start being genuinely important, because what the fleet carried west was substantially Canarian: sugar cane, vines, goats, pigs, and the men who knew how to grow and mind them.

The third voyage in 1498 and the fourth in 1502 called here too. So did nearly everything else. Under the Spanish crown's shipping regulations, the Canaries were the authorised staging point for the Atlantic route, and the islands spent the next three centuries as the last European port before the Americas — and one of the first on the way back.

What the islands sent west

The most consequential export was not a plant but a system. The islands had spent the last decades of the fifteenth century building an economy on sugar, worked by enslaved Africans and Guanches on plantations financed by Genoese and Castilian money. That whole model — cane, mill, enslaved labour, export — was carried to Hispaniola and then across the Caribbean and Brazil, often by people who had learned the trade here. It is the darkest and most important part of the story, and it has its own page: sugar, slavery and the early colony.

Traffic went the other way as well. Potatoes, maize and tomatoes came back through these ports, and the islands' long relationship with the Americas produced a two-way migration that ran into the twentieth century — the returning emigrants known as los indianos, whose money built half the grand houses in Santa Cruz de La Palma.

What you can actually visit

The bottom line

Columbus did not discover the Canaries, did not conquer them and did not stay long. What he did was make them permanently important: after 1492 these islands were the hinge between Europe and the Atlantic world, and everything about their later history — the sugar, the wine trade, the pirates, the emigration — follows from that position.

Stand in the courtyard in San Sebastián with a hand on the wellhead and the scale of it lands properly. Then go and look at the rest of what La Gomera has, which is considerably more than one very famous departure.