Scientists may have found the world's largest dinosaur footprint in a remote area of Australia's northwestern coastline.
The footprint - measuring almost 1.7m (5.6ft) - from a giant sauropod dinosaur was among 21 types of tracks found on the Dampier Peninsula in Western Australia, more than 1,000km (621 miles) from Darwin.
The rocks there reportedly date back between 127 and 144 million years, older than previous dinosaur fossil discoveries in Australia.
"They are bigger than anything that has been recorded anywhere in the world," said Steve Salisbury, the lead author of a joint study by the University of Queensland and James Cook University.
The researchers used drones and light aircraft to take photos and measure the tracks in the area, which is known for its challenging terrain, weather and tides.
Dr Salisbury said: "What makes it really tricky is that the rocks where the tracks occur are only in the intertidal zone.
"They are under water half the time and there are daily tides of up to 10m."
Sauropods were four-legged plant-eaters with long necks and tails, pillar-like legs and huge bodies.
The scientists also found tracks from six types of meat eaters and the first evidence of armoured stegosaurs.
The study came about thanks to the local indigenous Goolarabooloo people, who have known about the tracks for generations.
They feared the footprints on James Price Point would be lost after it was chosen as a potential site for a liquid natural gas project.