I had less than 24 hours in Singapore when I visited in September 2012, but there was no way I was going to miss the Singapore Botanic Gardens. Accordingly, early in the morning the day after I arrived, I woke up and took a short subway ride to the gardens. The morning was humid, and a light mist rose from the trees as I entered the gardens. Fellow early risers were practicing tai chi on one of the vast lawns. I wandered around the grounds, admiring the trees and lakes, until the jewel of the site, the National Orchid Garden, opened. The orchids were exquisite, the blooms open in a profusion of red, orange, pink, and purple petals. The orchid garden requires a small entry fee, but it was well worth the expense. Singapore Botanic Gardens was inscribed on the World Heritage Site list as a tropical botanic garden that has proven vital for research and plant conservation -- particularly in supporting the cultivation of rubber on the Malay peninsula. The gardens are also Singapore's first World Heritage Site, and I think they are a beautiful addition to the list.
Logistics: The Singapore Botanic Gardens are easy to reach via subway (Botanic Gardens MRT station on Circle or Downtown lines), bus, or private transportation.