From the 1880's until today, model steam engines are very popular toys, and not only for kids. In the late 19th century, model steam engine manufacturers such as Bing introduced two types of miniature steam engines: mobile (boats and locomotives) and stationary steam engines. Later, fire engines, steam rollers, wagons & traction engines began to appear. Around the mid 20th century, there were many toy firms producing model steam toys and engines.
Started by Peter Doll and and Isodor Sondhelm in 1898. Doll had a wide variety of both steam engines and steam toys, and were widely distributed to the US and UK.