What is "trolley park"

n. 1 (context US English) a recreational area at the end of a streetcar line 2 (context British English) a holding area for supermarket trolleys

In the United States, trolley parks, which started in the 19th century, were picnic and recreation areas along or at the ends of streetcar lines in most of the larger cities. These were precursors to amusement parks. These trolley parks were created by the streetcar companies to give people a reason to use their services on weekends. These parks originally consisted of picnic groves and pavilions, and often held events such as dances, concerts and fireworks. Many eventually added features such as swimming pools, carousels, Ferris wheels, roller coasters, sports fields, boats rides, restaurants and other resort facilities to become amusement parks. Various sources report the existence of between 1,500 and 2,000 amusement parks in the United States by 1919.