Held in conjunction with Singapore's World Water Day celebrations, the event, which is in its third year, drew participants from 69 countries, including Kenya and Iceland.
Minister for the Environment and Water Resources Vivian Balakrishnan, the guest of honour, told runners at the start line: "This run you are about to go on is truly unique.
You are not going to get another one (like it) in Singapore, or even this region."
For the first time, booklets containing information on the former rail corridor were also handed out to participants.
The booklet, which was put together by the Nature Society (Singapore) and Singapore Heritage Society, contains, among other things, a map of the Green Rail Corridor and descriptions of the heritage locations along the stretch.
In 2010, nature and heritage groups asked the Government to conserve what they termed the Green Corridor.
The 26km strip of former railway land, which was returned to Singapore in 2011, slices through Singapore from Woodlands in the north to Tanjong Pagar in the south.
It was previously used by Malaysia's Keretapi Tanah Melayu or KTM railway.
Some participants in yesterday's run also carried jerry cans of water along the 10.5km stretch from the Tanjong Pagar railway station in Keppel Road to Bukit Timah railway station, where the race ended.
It was to experience what it was like for people in developing countries who have to travel long distances to fetch water.
This article was first published on Mar 9, 2015.
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