Have you ever wondered how train tracks are laid? The construction team at Mernda explains.

The rail is delivered from South Australia in 27.5 metre lengths before being fed through a production line in Spotswood, Victoria.

Once turned into 165 metre lengths, workers position the rail onto special trains for delivery around the state, to projects such as the Mernda Rail Extension.

When they arrive at the site, dedicated rail trains travel along existing track and lay down the new lengths.