NParks will be holding two free public tours of Singapore's Nature Ways on Saturday and Sunday.

Nature Ways are routes planted with specific trees and shrubs to help animals such as birds and butterflies move from one green area to another. There are currently four such routes in Singapore, located in Yishun, Tampines, Admiralty and Kheam Hock.

The first tour of Yishun Nature Way on Saturday will include a guided walk to spot butterflies and viewing heritage trees in the Seletar area. The second tour, of Tampines Nature Way on Sunday, includes visiting a butterfly garden as well as Changi's heritage trees. Both begin at 8.30am.

The tours are organised in conjunction with the release of a children's book, titled Secrets of the Swamp, available in all bookstores from Friday.

To sign up, members of the public can email nparks_nature_ways@nparks.gov.sg with their name, number of family members of friends, contact number and the name of the tour. Each tour will have a maximum of 35 participants and spaces are given out on a first-come first-served basis.