Thian Hock Keng Temple
The oldest Hokkien temple in Singapore, dating back to 1821, although the structure was thoroughly refurbished in 2000. The brightly colored, elaborate facade was constructed with ironwork from Scotland, tiles from England and the Netherlands, and dragon-ornamented granite pillars from China.
Pinnacle@Duxton Skybridge
Singapore's tallest public housing project has a 50th story viewing deck that offers some of the best city views around at a fraction of the cost of the Singapore Flyer. $5, but payment must be made by ez-link card; enter via Block 1G, Level 1 next to bus stop.
Chinatown Heritage Centre
An excellent museum chronicling how Chinatown came to be and the privation suffered by early migrants. The centre is on the left if you walk straight from the Pagoda St exit of Chinatown MRT station.
Sri Mariamman Temple
Singapore's oldest and most important Hindu temple and worth a visit for the intricately carved gopuram statuary above the entrance, which gave adjacent "Pagoda Street" its name. This is an active temple, so take off your shoes and don't disturb the worshippers. The Thimithi fire-walking festival is held here one week before Deepavali, usually Oct/Nov.
Chinatown's primary attraction is the town itself, composed as it is of restored shophouses full of strange little shops selling everything from plastic Buddhas to dried seahorses. Wander at random and see what you can find!
Red Dot Design Museum
Formerly the traffic police HQ, now a design center painted firehouse red with a museum devoted to contemporary design.
Buddha Tooth Relic Temple
Towering above southern Chinatown, this four-story temple was completed only in 2007. The imposing main hall hosts a 27-foot statue of Maitreya Buddha, and the sacred relic itself, reputedly one of Buddha Shakyamuni's teeth, can be found on the fourth floor visible only during daily ceremonies at 9-11 AM, 2-3:30 PM, 6:30-8 PM. On the roof is the 10,000 Buddhas Pagoda, hosting a large Tibetan-style prayer wheel.
Jamae Mosque
One of Singapore's oldest mosques, built in the 1830s by Tamil Muslims in an Indian style. Note the stepped minarets outside.