National Geographic Society has chronicled scientific expeditions, explorations, archaeology, wildlife and world cultures for more than 100 years, amassing a collection of 11.5 million photos and original illustrations.

A small selection of that massive archive - 240 pieces spanning from the late 1800s to the present - will be sold at Christie's in December at an auction expected to bring about $3 million, the first time any of the institution's collection has been sold.

Among the items are some of National Geographic's most indelible photographs, including that of an Afghan girl during the Soviet invasion of Afghanistan, a portrait of Admiral Robert Peary at his 1908 expedition to the North Pole, a roaring lion in South Africa and the face of a Papua New Guinea aborigine.

Paintings and illustrations include N.C. Wyeth's historical scene of sword-fighting pirates, Charles Bittinger's view of Earth as seen from the moon, and Charles Knight's depictions of dinosaurs and other prehistoric animals...,