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From the mid-19th century，horse-drawn trams（or horsecars）were used in many cities around the world.In the late 1880s electrically-powered street railways became technically feasible after the invention of a trolley system of collecting current by American inventor Frank J.Sprague who installed the first successful system at Richmond，Virginia.They became popular because roads were then poorly surfaced，and before the invention of the internal combustion engine and the advent of motor-buses，they were the only practical means of public transport around cities.
The light rail systems built in the 19th and early 20th centuries generally only ran in single-car setups.Some rail lines experimented with multiple unit configurations，where streetcars were joined together to make short trains，but this didn’t become common until later.When lines were built over longer distances（typically with a single track）before good roads were common，they were usually called interurban streetcars in North America or radial railways in Ontario.
In North America，many of these original light-rail systems were decommissioned in the 1950s and onward as the popularity of the automobile increased.Though some traditional trolley or tram systems still exist to this day，the term“light rail”has come to mean a different type of rail system.Beginning in the 1980s，some cities began reintroducing light-rail systems that are more like subway or metro systems that operate at street level.These light-rail systems include modern，multi-car trains that can only be reached at stations that are spaced anywhere from a couple blocks to a mile or more apart.Some of these systems operate within roadways alongside automobile traffic，and others operate on their own separate right-of-way.
As with other rail systems，the rail gauge has had a lot of variations，but today standard gauge is dominant.Narrow gauge was common in many earlier systems，though as systems merged or died out，old lines were often upgraded，removed，or replaced.Some systems still use other track gauges，however.
Questions for Discussion
1.What did the light rail systems built in the 19th and early 20th centuries look like？
2.When did some cities begin reintroducing light-rail systems that are more like subway or metro systems that operate at street level？