Frederick and Gerrit Braun, 41, have spent 500,000 hours and the equivalent of more than £8million working on it.
Their creation is on display to the public and is so vast they have to employ more than 160 people just to show visitors around.
Their 'Miniatur Wunderland' is split into six regions, including America, Switzerland, Scandinavia, Germany and the Austrian Alps.
Each region boasts detailed models of some of the world's most famous landmarks.
The American section is home to giant models of the Rocky Mountains and Mount Rushmore; the Swiss section has a mini-Matterhorn; and the Scandinavian part has a 4ft long passenger ship floating in a 'fjord'.
The brothers estimate the enormous track will be completed in 2014, when it will cover more than 1,800 square metres and feature almost 13 miles of track.
Today, their model railway comprises 700 trains with 10,000 carriages, 900 signals, 2,800 buildings and 160,000 individually designed figures.