In the 1890s, industrialist Andrew Mellon owned a trolley line that carried workers to the Andrew Carnegie Steel Works -- later the U.S. Steel Homestead Works -- and ended at property owned by Anthony Kenny.

But Mr. Mellon wanted people to ride the trolley on their days off, too, so he leased 145 acres from Mr. Kenny to build Kennywood.

The original amusement park consisted of a man-made lake and three structures: a picnic pavilion, a merry-go-round and a dance pavilion.

The first roller coaster was the 13-mph, figure-eight-shaped Toboggan, built in 1902 and later renamed Gee Whiz Dip the Dips.

In 1906, two associates of Mr. Mellon, A.S. McSwigan and F.W. Henninger, took over Kennywood, and their families operated the park until last year when a proposal was accepted to sell Kennywood to London-based Candover Investments.

The first Racer was built in 1910, followed by the Speed-O-Plane in 1911. Three other coasters were added in the 1920s: Jack Rabbit, Pippin and a new Racer that replaced the 1910 version.

In 1927, Kiddieland was erected at its present site. Two original rides remain from the era: the merry-go-round and the ferris wheel.

The Great Depression was hard on the park, but dancing helped keep it in business. Live performances by dance bands would last for the next 20 years.

Noah's Ark made its debut in 1936, the same year as the Great Pittsburgh Flood.

"If I had been the marketing director, I would have said I knew the flood was coming, that's why we built the ark," said Andy Quinn, resident historian and director of community relations.

Popular rides added in the 1950s included the Hurricane, Looper, Rotor, Wild Mouse and the Octopus.

The Turnpike ride was built in 1966, followed two years later by the Thunderbolt.

A fire in 1975 damaged a walk-through attraction that had been converted from the original dance pavilion, and it was not replaced.

In 1987, the park was designated a national historic landmark, one of only two amusement parks to be so honored.

The park undertook its largest expansion in 1995 by adding Lost Kennywood, which pays tribute to the old "electric parks" from the turn of the 20th century with rides, concessions and games reminiscent of the era.

Mr. Quinn said the new owners have promised a big ride will be added in 2010 or 2011 but have not revealed what it will be.

All of the employees hope it's another roller coaster, he said.