Conservationists at Persepolis, Iran’s most iconic ancient site, and the ceremonial capital of the Achaemenid Empire, are having to contend with stone-eating lichens, which have been eroding millennia-old monuments. A UNESCO World Heritage Site since 1979, Persepolis features over 1700-year-old colossal sculptures and intricate stone reliefs of ancient Persian kings, nobles and deities. The aim […]