A metal church signed by Gustave Eiffel, a French bakery more than a century old, wooden houses with galleries facing the Sea of Cortez: Santa Rosalía is unlike any other town in Baja California Sur. This singularity has an unusual history behind it. At the end of the 19th century, a French mining company, El Boleo, set up here to mine copper and built an entire town to its own plans. Ships, generally small ones, dock in the modest harbour basin, a few steps from the first streets, where the ferry linking the peninsula to Guaymas, on the mainland side of the gulf, also arrives.

A town born of copper

From 1884, the El Boleo company laid out roads, set up workshops, built warehouses and housed its workers in orderly neighbourhoods on the side of the mesa: French managers up top, the Mexican workforce near the facilities. The company's name comes from the "boleos," the copper-rich nodules found in the surrounding hills. From the approach, the town's silhouette surprises: no white towers or domes, but dark sheds, metal frameworks and two desert plateaus squeezing the town in their mineral grip. Walking from the waterfront, you spot remnants of this industrial era everywhere: rusted iron structures, furnaces, machines and mine carts left in place, as if the mine had only just closed. The whole gives the town a raw, almost cinematic character that intrigues from your very first steps under the dry sun of the gulf.

A monument from a Paris workshop

In the centre stands the town's most famous curiosity: Santa Bárbara, a prefabricated building of galvanized iron designed by Gustave Eiffel in 1884. Originally conceived as a dismountable prototype for tropical colonies, it was shown at the Paris World's Fair in 1889, the same year as its creator's tower, before being bought by an El Boleo executive, shipped by boat and reassembled here in 1897. The cool, bright interior is worth stepping into: few places in the world let you pray beneath vaults of riveted steel, and the contrast between the rigour of the metal and the gentleness of the place leaves no one indifferent.

Wooden galleries and French bread

Around the church, the streets tell of the French presence in other ways. The period houses, built of wood with verandas and tin roofs, evoke a colonial trading post in the tropics more than a Mexican village; several still display their faded colours, sea green, sky blue, straw yellow. On the main street, the El Boleo bakery has carried on a French-style baking tradition since the mining years: locals and visitors line up for golden baguettes and Mexican sweet breads. The smell alone justifies the stop, and a pastry bought there goes well with the walk to the waterfront, where fishermen and pelicans share the jetty.

The rhythm of a port call

1. From the quay, walk to the main street and the bakery.
2. Continue to Santa Bárbara and its neighbourhood of wooden houses.
3. Climb toward the old mining sites and their viewpoints over the gulf.
4. Finish along the malecón, as the low light gilds the tin roofs.

Back to sea

Santa Rosalía can be discovered in two or three hours of leisurely walking, and yet it holds a special place in passengers' memories. You've seen a steel place of worship born in Paris, tasted bread inherited from French miners and walked past machines frozen for a century. Climbing back up the gangway, you catch yourself thinking back on this improbable destiny: a piece of industrial France set on the desert coast of the Gulf of California, and still very much alive.