For Spain and for Sherry: Bulls Mark 50 Years of Roadside Ads

Jet black, 14 meters high and weighing 4,000kg, the iron silhouettes of Spain's most famous animal that loom large over the country's motorways are celebrating their 50th birthday.

When the bulls started life as an advertising campaign for sherry nobody could have imagined that they would become the unofficial symbol of Spain. But half a century on you can find the image on flags, T-shirts and guidebooks, at sporting events and national festivals. In a scene from the 1992 film Jamón, Jamón, Penélope Cruz and Javier Bardem make love underneath one of the bulls. Wherever you see Spain, the bull is never far behind.

The Osborne sherry company, founded by an English immigrant to Andalucía in the late 18th century, originally placed the bulls on roadside bends to catch drivers' attention. They used to bear the company logo and the name of its Veterano brandy, but the words were removed in 1988 after it was ruled that they were distracting drivers. By then the silhouettes were so famous that the company decided drivers would need no reminding of what the bulls were promoting.

In the mid-90s a new law banned the siting of structures too close to roads, so Osborne moved its bulls to hillsides overlooking the motorways. But they still faced legal challenges. By then, though, the public had so grown to love the bulls that even the supreme court could not sanction their removal. In 1997 judges ruled that the bulls had "become part of the landscape".

Although Catalan nationalists removed the bulls from the region due to their association with Spain, about 90 are still to be found dotted across the country.

This year Osborne is marking their half-century by inviting 50 Spanish stars to paint small replicas of the bulls, which will be auctioned. The artists include Real Madrid footballers, model Inés Sastre and flamenco dancer Joaquín Cortés. So we see the bulls dressed in formal attire, wearing a frilly red skirt and challenging a naked female bullfighter.