The largest group of carol singers consisted of 15, 111 participants and was achieved by the Hong Myung-bo Foundation (South Korea) during the Hong Myung-bo Charity Soccer Game in Seoul, South Korea, on 25 December 2010.

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Back at Ko Hong, just around the corner from Ao Bo Lae, the otherwise continuous circle of limestone cliffs that surround the island opens up slightly.

BBC: The perfect trip: Thailand