This is one of Singapore's several offshore islands which has been left more or less untouched by urban development. Getting there is all part of the fun - take a bus or taxi to Changi Point jetty, which is about 40 minutes from the city centre.
Then, take a bum-boat ride to the island. The boats leave when they're full and charge SG$ 1.50 for a one-way ride. There is no admission fee to the island.
Spend the whole day on Pulau Ubin, dividing your time between biking on the rocky trails, bird-watching, swimming on the beach and trying out the fresh seafood.
Bikes can easily be rented , though don't expect a state-of-the-art 10-speeder; the rusty, rickety machines on offer are part of the island's charm. You'll pass mangrove swamps, coconut and rubber plantations, an unused quarry lake, even a Buddhist temple. Don't be surprised to see wild pigs roaming the island, or huge flying fox bats at night.