The Indiana Convention Center draws a colorful cast of characters during special conventions throughout the year, including costumed gamers for Gen Con, uniformed officers representing fire departments around the country and blue-jacketed teenagers as part of the annual Future Farmers of America convention, the largest youth conference in the country.

Convention demand has helped spur the need for four expansions of the Convention Center, the latest was completed in January 2011, nearly doubling its space to more than 566,000-square-feet (roughly the size of about 10 football fields).

Designed by Indianapolis’ RATIO Architects, the $275 million expansion had to encapsulate the original 1972 structure. The new entrance, a glass cube supported by four white steel columns and a large canopy, was designed to welcome in visitors. When the glass is illuminated, you’ll see a myriad of colors inspired by the theme of the convention taking place inside.

Taking up about 10 city blocks, the Convention Center has a series of skywalks making it possible for convention-goers to connect to 12 downtown hotels and the Circle Centre Mall. Plus, the new pedestrian-friendly, temperature controlled walkway links to Lucas Oil Stadium.

Lucas Oil Stadium to the south of the Convention Center, replaced the RCA Dome, once located on what is now the latest expansion of the Convention Center. This is where Peyton Manning began his NFL career. Because construction couldn’t interfere with the Colts season, it made for a tight construction schedule. As soon as the last game was played of the 2009-2010 season, the dome was imploded.

Remnants of Indianapolis’ first ever NFL stadium can be found around the city. Lockers were donated to local high schools, the dome’s 257-ton, eight-acre fiberglass roof was recycled and has been reused as park shade awnings. Local artists have created wallets, clutches and messenger bags made from the roof material.

That’s not the only sustainable aspect of the Indiana Convention Center. Any remaining food left from special events and conventions is donated to Second Helpings, a food rescue program near downtown, which provides training for chefs and provides food for homeless shelters and missions.