The Endeavour nearly wrecked on the Great Barrier Reef

During his first journey, after touching down in Australia, Cook steered his ship north and made for the Dutch harbor of Batavia. He was unaware that he was sailing directly into the Great Barrier Reef's razor-sharp coral structures because he was in an uncharted region. His ship Endeavour collided with a coral reef on June 11, 1770, and started to take on water, putting the lives of his crew and the priceless maps of his Pacific discoveries in peril. His journey was delayed by over seven weeks as repairs were made to the severely damaged ship on the shore (near the docks of modern Cooktown, Queensland at the mouth of the Endeavour River).

The crew's interactions with the local Aboriginal population were generally amicable until Cook ordered bullets to be fired during a fight over green turtles, leaving one local lightly wounded. To lessen the weight of the ship, Cook's crew frantically pumped water out of the holds and tossed cannons and other equipment overboard. They even attempted to patch a hole in their hull using an old sail. They managed to plug the leak after more than 20 frantic hours and limped toward the Australian coastline. Cook's ship wouldn't be seaworthy once more until nearly two months had passed during repairs.

The journey continued on August 22, 1770, at approximately noon, Cook named it York Cape without getting off the ship (now Cape York). Cook turned west after leaving the east coast, guiding his wrecked ship through the treacherously shallow waters of Torres Strait. Cook was looking for a vantage point when he noticed a steep hill on a nearby island. Cook hoped to view "a route into the Indian Seas" from the top of this hill. Cook gave the island the name Possession Island, claiming that it was British territory and that the entire coastline he had recently discovered.