If I remember correctly, after the ice slides, a king or queen or someone loved them so much, that they had wheels put on the sleds so they could slide down the hill all year down.
The origins of the modern coaster come from La Marcus Thompson, and his Gravity Pleasure Switchback Railway, built at Coney Island in the late 1800s. Then others took the idea and ran with it, primarily John Miller, and those who invented upstops, etc.
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- Peabody