Singapore Night Safari is the first and maybe the only night zoo. There is a night animal show that starts at 7.30, 8.30, 9.30 pm but you'll need to be there 30 minutes ahead of time to get a place, its that crowded. Walking around the zoo will take you easily 3 hours. No flash allowed when you're taking photography, so bring along your f1.2 prime and 2.8 zooms. Entrance fee is $22.
Our Singapore Zoo is similar to the San Diego Zoo with open concept. Entrance fee is S$16.00 for adults. It opens at 9 am and closes at 6pm.
The Singapore Bird Park is another worthwhile place to visit with all kinds of birds flying freely and a man made waterfall thats a 100 feet high.
The River Safari is new and features the giant monster fishes around the world such as sturgeons, arapaima, and the stars of the show 2 pandas.
Each can take at least 3 hours to tour and if I have to choose only one, I would rate their value worthiness as 1) Singapore Zoo 2)Bird Park 3) River Safari 4) Night Safari. Note the Singapore Zoo, River Safari and Night Safari is in the same location within walking distance and the Bird Park is somewhere else.