World's largest model railway "Northlandz", in Flemington, New Jersey, USA. [Photo/icpress.cn]

Even big kids would struggle to outgrow this toy as it is the world's largest model railway named Northlandz, in Flemington, New Jersey, the United States.

It was painstakingly constructed by hand and took more than 16 years to complete. Bruce Williams Zaccagnino started the project as a hobby in his basement, but the impressive model now boasts 100 trains, 400 bridges and more than eight miles of track.

The popular tourist attraction - which has been open to the public since 1997 - contains more than 3,000 miniature buildings, set up in idyllic cities and villages, as well as 50,000 street and 40 foot bridges spanning vast canyons, all of which Bruce designed and built on his own.