By Mary Wisniewski

CHICAGO (Reuters) - An iconic 15-story Ferris wheel, which had been part of the Chicago skyline for 20 years, will be trucked across the Mississippi River and rebuilt like a "big Erector Set" at a Missouri amusement park, officials said on Friday.

The Ferris wheel, modeled after the one built for the 1893 World's Columbian Exposition, also known as the Chicago World's Fair, can hold 240 passengers on 40 gondolas.

The wheel is going to The Track Family Fun Parks in the tourist-friendly town of Branson, Missouri, swapping a view of Lake Michigan for one of the Ozark Mountains, said Track Chief Executive Craig Wescott.

Branson officials approved the wheel, 50 feet (15.2 m) taller than the city's 100-foot (30.5 m) height limit for structures, on Thursday night.

Wescott said trucks will carry the disassembled wheel to Branson next month, and it will be ready by Memorial Day at a cost of $2.5 million.

"This is oversimplified, but it's like a big Erector Set," said Wescott, referring to the children's building toy.

Chicago is building a new 196-foot-tall (60 m) Ferris wheel on Navy Pier this year, a popular multi-use tourist attraction which is celebrating its 100th anniversary.

There has been a boom in city observation Ferris wheels in the last few decades, including the 443-foot London Eye (135 m) unveiled in 1999; the 525-foot Star of Nanchang in China (160 m) put up in 2006, and the 550-foot High Roller (168 m) in Las Vegas in 2014.

Coincidentally, the original 1893 Chicago wheel, built by engineer George Ferris, also was taken to Missouri and featured at the 1904 World's Fair in St. Louis. It was later demolished.

(Editing by Bernadette Baum)