The Great Barrier Reef, off Queensland, Australia, is the world's largest coral reef system: more than 2,900 individual reefs and 900 islands stretching over 2,300 kilometres. It is the biggest single structure made by living things, built by billions of tiny coral polyps, and visible from space. A 2020 study found that over half of its coral cover was lost between 1995 and 2017, driven by mass bleaching from warming seas, runoff of pollutants, and outbreaks of the crown-of-thorns starfish. Much of the reef is protected by a marine park that limits fishing and tourism, which brings in more than AUD 3 billion a year.

Israeli reports also say the cabinet directed the military to prepare for a possible new attack on Iran.

Angkor, near Siem Reap in northern Cambodia, was the capital of the Khmer Empire, which ruled much of mainland Southeast Asia between roughly the 9th and 15th centuries. At its height the city spread across about 3,000 square kilometres, making it the largest pre-industrial city on Earth by area. Its growth depended on water: huge reservoirs called barays, along with canals and embankments, stored monsoon rain and carried it to rice fields. That system let farmers harvest more than once a year and fed a very large population through the dry season. The temple complex of Angkor Wat, built in the early 12th century, is the best-known monument and still stands at the heart of the park.