The Wonder Wheel is a 150-foot-tall (46 m) eccentric Ferris wheel at Deno's Wonder Wheel Amusement Park at Coney Island in the New York City borough of Brooklyn. The wheel is located on a plot bounded by West 12th Street to the west, Bowery Street to the north, Luna Park to the east, and the Riegelmann Boardwalk to the south. As with other eccentric Ferris wheels, some of the Wonder Wheel's passenger cabins are not fixed directly to the rim of the wheel, but instead slide along winding sets of rails between the hub and the rim.

Built in 1920 as one of several Ferris wheels on Coney Island, the Wonder Wheel was designed by Charles Hermann and operated by Herman J. Garms Sr. and his son Fred for six decades. Despite the subsequent economic decline of Coney Island, the Wonder Wheel continued to operate each summer through the 20th century. In 1983, Herman Garms's son Fred sold the ride to the Vourderis family, who restored the attraction and continue to run the wheel as of 2023^[update]. The New York City Landmarks Preservation Commission designated the Wonder Wheel as an official New York City landmark in 1989, and minor modifications were subsequently made to the attraction.

At the time of the Wonder Wheel's construction, Coney Island was one of the largest amusement areas in the United States. The first Ferris wheel in Coney Island was built for nearby Steeplechase Park in 1894 and was erroneously billed as "the world's largest". Several variations of the Ferris wheel were erected in the neighborhood in the 1900s and 1910s. The Wonder Wheel was unusual in that only one-third of its 24 cars were stationary, while the other two-thirds rolled on tracks within the wheel itself.

The Wonder Wheel was designed by Charles Hermann as an improvement on G.W.G. Ferris's giant wheel, and it was built for Herman J. Garms Sr. between 1918 and 1920 by the Eccentric Ferris Wheel Company. Coney Island landowner William J. Ward provided the land for the Wonder Wheel's construction. Garms, who had no formal financial experience, sold stock to family, other Coney Island business holders, and steelworkers. Hermann sold all his shares in the wheel to raise money for construction and operation. Alfred (Fred) Garms, Herman Garms's son, recalled that his father employed anyone who was willing to help erect the ride, teaching them how to construct the wheel. After the local ironworkers' union heard about the project, they attempted to force the workers to join the union. The elder Garms named all of the workers as stockholders of the Eccentric Ferris Wheel Company, preventing them from being forced to unionize.

The wheel first opened on Memorial Day in 1920. Hermann originally called it the "Dip-the-Dip", promising to combine in his new invention "the thrill of a scenic railway, the fun of a Ferris wheel, and the excitement of the Chute-the-Chutes". To help with the Wonder Wheel's upkeep, the Garms family lived under the Wonder Wheel during the summers. With the success of the Wonder Wheel, the Eccentric Ferris Wheel Company hoped to build more "wonder wheels" on the East Coast of the United States by the mid-1920s. Fred Garms worked on the ride as a ticket operator during the summer in the 1920s, when he was a child. By the time Fred had graduated high school in the early 1930s, he worked on the ride year-round, maintaining it. After the ride's construction cost had been paid off, Herman Garms bought out most of the Eccentric Ferris Wheel Company's stockholders, then reduced the size of the corporation to a small number of people.

The Wonder Wheel was damaged in a 1933 fire that also burned down several attractions nearby. The wheel was also known as the "Eccentric Ferris Wheel" before being renamed the Wonder Wheel by 1940. During World War II, the lights on the Wonder Wheel were turned off due to a blackout order affecting Coney Island. The ride set an all-time daily ridership record on July 4, 1947, when it carried 14,506 passengers. The Wonder Wheel continued to operate through the 1950s, and it recorded its ten-millionth lifetime passenger in 1952. One account from 1953 described the ride as carrying thousands of passengers, with clients coming from the South and along the East Coast. At the time, although Herman Garms still owned the ride, Fred was the manager, and there were multiple longtime employees on payroll. The New York City Department of Buildings inspected the wheel each year, as each amusement ride in Coney Island could operate only with a license that expired every March, and the licenses could not be renewed without a building inspection.

By the 1960s, Fred Garms had taken over operation of the Wonder Wheel. Coney Island started to decline during the mid-20th century, and by 1964, it had seen its lowest number of visitors in 25 years. Despite subsequent attempts to redevelop the area, the Wonder Wheel continued to operate. Furthermore, it had not had any significant incidents in its history, making it a relatively well-off ride when other Coney Island attractions were closing. To discourage crime, the wheel and surrounding attractions were protected by two German Shepherds at night: one at the wheel's base and the other on an adjacent roof; during the day, the dogs rode around in one of the Wonder Wheel's cars, where the operator provided food and water for them. Off-duty security officers were also hired to prevent confrontations with the mafia. By the 1970s, the Wonder Wheel had carried more than 20 million lifetime riders. To keep up with expenses, the Wonder Wheel raised ticket prices significantly, from $0.50 in 1976 to $1.25 by 1981.

Fred Garms was looking to sell the wheel by 1983, as he was getting older and unable to manage the wheel. Denos D. Vourderis had long been interested in buying the wheel from Garms. Vourderis was in a hospital recovering from a stabbing attack when Garms approached Deno's son Dennis on the possibility of purchasing the ride. On June 7, 1983, Vourderis bought the Wonder Wheel from Garms and his cousin Walter Kerner Sr., and it became "Deno's Wonder Wheel". The New York Times wrote that the only maintenance instructions given to the Vourderis family were the words "Good Luck" scribbled on a cardboard cigarette box. The ride cost Vourderis $250,000. He stated that part of the wheel's allure had come from when he had proposed to his future wife Lula atop the wheel 36 years prior to the purchase: he had promised to give the wheel to his wife as a future gift.