He studied law at his father’s wish, but his interest led toward exact sciences, he chose physics as the subject of his studies. His famous experiments in gravitation made him world-renowned. He proved the equivalence of gravitational and inertial mass to an accuracy of two hundred million parts. This extraordinary precision was achieved by means of the Eötvös pendulum a device constructed for this purpose. Eötvös was well recognized in his lifetime, a crater, on the unseen side of the Moon was named after him. He was a splendid alpinist. In recognition of his mountain climbing accomplishments the second highest peak in the Cadin group was named Cima Eötvös. Our book introduces, aside from a learned physicist, the traveler, excellent sportsman a mountain climber and primarily the true photographer. Eötvös regularly took mostly stereo photos of his experiments in physics, as well as his mountain climbing tours. The volume is a selection of this hitherto unknown legacy. The photographs are accompanied by quotations from his diaries and letters.