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go to the Guardian.com forward slash long read. They take you out of life, out of time. A journey into Spain's astonishing cave paintings, written and read by Stephen Feeleyn. The aurochs, the mammoth and the steppe bison are long extinct, but their painted likenesses

still look relatively fresh across the walls and roofs of Altamira. Or so said Diego Garate Maidagan, who is one of the very few humans allowed to enter that exalted cave in northern Spain.

I met Garate last summer in a small Basque village called Gauteges Arteaga.

A professor of prehistory and paleolithic art at the University of Cantabria,

he told me he'd been inside Altamira as recently as the week before,

furthering his lifelong investigations of the prepwork, tools, and methodologies

developed by early Homo sapiens painters.

About 34,000 years ago, our distant ancestors began making frescoes with kioskuro effects

through that suite of subterranean vaults, which remained in use for many millennia until

the cave mouth was sealed by a rockfall.

The best part of a geological epoch passed before a curious gundog clawed its way across the threshold in 1868, leading a succession of witnesses into the first such prehistoric gallery

ever seen by modern eyes. The technique on display at Altamira seemed much too sophisticated for troglodytic nomskulls,

as paleolithic people were then assumed to be, and self-appointed experts from France

initially declared the whole thing a hoax. Those accusers were to look pretty stupid

when similar caves were found in their own country.

Pablo Picasso is said to have visited,

...