More than 70 years after the original cave was discovered, France will unveil a stunning real-to-life copy of the 18,000 year-old Lascaux cave, which cost €66 million and took four years to create. The last of four boys who discovered the Lascaux cave paintings, a stunning display of prehistoric art in southwest France, will visit a new replica of the site Saturday. Simon Coencas, now 89, will join President Francois Hollande for the inauguration of the display at a visitors' centre in Montignac, a village at the foot of the hills where he discovered the cave as a teenager. More than seven decades after he got his first look at the site, Coencas will -- health permitting -- revisit a complete copy of the caves. The tale of how he and three friends discovered the site, in the Dordogne region…