Outdoor Toys, Structures 
Model railroading (US) or Railway modelling (UK) is a hobby in which rail transport systems are modeled at a reduced scale, or ratio. more...
The modeled world includes rail vehicles (locomotives and rolling stock), tracks, signalling, scenery (roads, buildings, vehicles, model figures and natural features such as streams, hills, canyons, etc.). The earliest forms of model railways are the 'Carpet Railways' which first appeared in the 1840s. Model trains are generally more realistic than toy trains.
General description
Involvement in the hobby can range from the possession of a train set to spending many hours and large sums of money on a large and exactingly executed model of a railroad and the scenery through which it passes, called a "layout". Hobbyists, called "model railroaders" or "railway modellers", may even maintain models large enough to ride (see "Live steam" and "Backyard railroad"). Model railroaders may find enjoyment in collecting model trains, building a miniature landscape for the trains to pass through, or operating their own railroad, albeit in miniature.
Some older scale models reach very high prices.
Layouts vary from the very stylistic (sometimes just a simple circle or oval of track) to the "absolutely realistic", where real places are modelled to scale. One of the largest of these is in the Pendon Museum in Oxfordshire, UK, where an EM gauge (same scale as OO but with a more accurate track gauge) model of the Vale of the White Horse as it appeared in the 1930s is under construction. The museum also houses one of the earliest scenic models ever made - the 'Madder Valley' layout built by John Ahern. This latter layout was built in the late 1930s to late 1950s and brought in the era of realistic modelling, receiving coverage on both sides of the North Atlantic in the magazines Model Railway News and Model Railroader during the 1940s and 50s. Bekonscot in Buckinghamshire is the oldest model village, and also includes a model railway, dating from the 1930s onward. The world's largest model railroad track in scale HO is Miniatur Wunderland in Hamburg, Germany, while the largest live steam layout, with over 25 miles (40 km) of trackage is Train Mountain in Chiloquin, Oregon, USA.
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