Looking at photos online, he knew he’d need a lens ... At the end of Hang Son Doong stood the Great Wall of Vietnam, a 200-foot barrier to be conquered by both ladder and rope climbing.

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We'll be back soon with more updates on the war in Ukraine ... during attacks against Ukrainian-held positions," they said. In pictures: Ukrainian troops carry out live fire tank exercise These ...

Series that offers listeners the chance to take a long, slow look at great artworks, photographed in incredible detail.