This is not Bermudian originally but Chinese or Japanese or both, many centuries old. (In July 2004, a Japanese garden with a structure almost identical to what in Bermuda is called a moongate, won a Silver Gilt prize at the Royal Horticultural Society show at Tatton Garden in the UK). The first plan for one in Bermuda was brought from a Chinese garden in 1860 by a local sea captain. He drew the design of a circular, ornamental wooden gateway to a garden or place of inner repose and, once back in Bermuda, built one of his own. It was copied. It has since been adopted by Bermuda as a national symbol. There are many now in Bermuda. The Bermuda version is built of Bermuda stone and often but not always used as an entrance to a garden. There is also a New England version, in granite, of the Chinese design, as the attached photograph shows.
Legend has it that people who walk through a Moongate, especially young lovers and honeymooners, are blessed with good luck. The real Oriental origin of the Moongate was almost completely lost locally when the former gardener of the Duke of Westminster in the United Kingdom was employed to lay out the grounds of the (former) Bermudiana Hotel in the 1920s being built at that time by the Furness Withy shipping group. This was the first of the Bermuda Moongates in hotel properties.