SOUTH GEORGIA ISLAND

Half a million king penguins, each standing three feet tall, pack shoulder to shoulder in mesmerizing colonies on this hundred-mile-long, glacier-studded island–reached by two days of sailing east of Chile’s Cape Horn. Millions of smaller seabirds nest on the island’s tussock-covered slopes, partly thanks to the largest-ever rat-eradication effort, completed on South Georgia in 2015. While drinking in the abundant birdlife, raise a glass to Ernest Shackleton at his final resting place.