You could spend days in this unique historic garden, a leafy oasis amid the high-rises of downtown Honolulu. Combine a tour of the garden with a trip to Chinatown (just across the street) to maximize your time and double your pleasure. The giant trees that tower over the garden’s main terrace were planted in the 1850s by William Hillebrand, a German physician and botanist, on royal land leased from Queen Emma. Today this 14-acre public garden, on the north side of Chinatown, is a living museum of plants, some rare and endangered, collected from the tropical regions of the world. Of special interest are 26 “Exceptional Trees” protected by state law, a large palm collection, a primitive cycad garden, and a hybrid orchid collection.