An open air market during the day, a famous red-light district area during the night. The eateries here offer some of the best food on the island.
Even given the nature of the district, the area is absolutely safe to walk in at night. There are numerous night clubs and bars where you can enjoy the vibrant Singaporean nightlife.
Wikipedia https://en.wikipedia.org/wiki/Geylang
Address 124 Geylang East Avenue 1, Geylang 380124, Singapore
Coordinates 1°19'6.254" N 103°53'13.462" E