With its 14,000-year-old red bison, Spain's Altamira cave paintings reopened to a lucky handful of visitors Thursday, giving them a glimpse of some of the world's most spectacular prehistoric art.
Renowned for vivid paintings of beasts and animal-headed humans, the Altamira cave closed in 2002 because scientists said the breath from crowds of visitors was damaging the prehistoric paint.
On Thursday it reopened for five members of the public, chosen by lot from visitors to a nearby museum that houses replicas of the paintings at Santillana del Mar, in the Cantabria region.
"There is a much stronger feel to the original cave compared to the replicas, although the paintings are very similar," said one of the five, law student Carolina Pardo, after emerging.
Another of the visitors, Andrea Vicente, said she was "very moved" by the experience.
"It gives you goose bumps," she said.
The five crept in wearing white masks and overalls and closed the door behind them as they headed underground to see the aeon-old masterpieces, on a visit lasting just 37 minutes.
Experts arranged the tour as an experiment to assess the impact on the paintings from readmitting the public after 12 years of studies.
The culture ministry said scientists would monitor the temperature of the air and rocks, humidity, carbon dioxide and any risk of contamination by micro-organisms during the visit.
- 'Earliest accomplished art' -
The highlight of the cave is a set of 14,000-year-old paintings of red and yellow bison plus horses, deer, humans with the heads of animals and mysterious symbols.
UNESCO listed the paintings as a World Heritage Site in 1985, as "masterpieces of creative genius and as humanity's earliest accomplished art".
The cave, whose walls are covered with colourful paintings over more than 270 metres (yards), was discovered in 1868 in northern Spain.
It has been dubbed the "Sistine chapel of Paleolithic art".
Experts say the cave was inhabited approximately 35,000 to 13,000 years ago.
The paintings are "exceptional testimonies to a cultural tradition and... outstanding illustrations of a significant stage in human history", UNESCO says in its listing.
The techniques of the paintings and realistic animal details mark "one of the key moments of the history of art", it says.
The caves are particularly well preserved and the style of paintings is unique to Cantabria, according to the world cultural heritage body.
During the closure, visitors have had to look at a nearby replica of the paintings, with only scientists allowed into the cave to carry out research.
In January, the foundation which manages the cave said it could reopen but only to groups of five people a week, and for just minutes at a time.
Overall 192 visitors will be allowed in by August, when experts will reassess the impact of the visits on the paintings.
"The aim is to analyse the impact of human presence on the conservation of the cave... to determine if continued access to the cave is possible or not," said junior culture minister Josa Maria Lassalle last month.