In 1879 a little girl lost interest in her father's digging and wandered further into a cave in Cantabria. She looked up and saw bulls on the ceiling. The father, Marcelino Sanz de Sautuola, a local landowner and amateur archaeologist, was digging in the floor of Altamira, a cave a hunter had stumbled on some years earlier. When he announced that the paintings were of the Ice Age, the experts of Europe laughed at him, and it was not until 1902, after similar paintings turned up in France, that the leading sceptic published a famous apology. Sautuola died long before that.
What those experts missed is still astonishing. The great ceiling at Altamira is a herd of bison painted in red, black and a warm ochre, using the natural bulges of the rock to give the animals a sense of volume, and it was made by people who lived here many thousands of years ago, in the Upper Palaeolithic. The date is a matter of continuing research, and the cave seems to have been used over a very long period. The original cave is now closed to ordinary visitors to protect it, but the neighbouring museum has an excellent full-size replica, the Neocave, and a good exhibition, and it is well worth the time. Check the booking rules for the museum before you ride out.
Santillana del Mar, less than a kilometre away, is a village of stone mansions and cobbled lanes where the writer Jean-Paul Sartre is said to have called it the town of three lies, since it is neither holy, nor flat, nor on the sea. It is one of the most handsome villages in Spain and, in summer, one of the busiest. Park at the edge, walk in early, and look at the Romanesque cloister of the collegiate church of Santa Juliana.
The riding in Cantabria is a different thing from the dry south. From Torrelavega, six kilometres away and the source of fuel, you can head west to the coast at Comillas, with its Gaudí villa, or south-east towards the green valleys of Cabuérniga and into the mountains. Roads are twisting and damp, the bends are tight and often covered in leaves, and rain is likely at any time of year. The Desfiladero de la Hermida, a deep gorge on the way to the Picos de Europa, is a rewarding day's ride, though it lies a good way to the west.