 The opening night of Wonderland Greyhound Park took place on June 12, 1935 and was attended by an estimated 5,000 people.Pansy Walker won the first-ever greyhound race in the park while $58,462 was wagered for the first evening.By July 21, after 17 race nights, the money wagered topped $100,000, never dropping below the figure for the duration of the park's 100 night inaugural season.