Three new domes have been put in place atop the Corn Palace tourist attraction in Mitchell.

The domes are part of a $7.2 million makeover of the building that's billed as the world's only palace dedicated to the grain.

The installation of the domes was delayed when city officials sought assurance that they could withstand South Dakota's weather. Crews last week added reinforcements.

About 200,000 tourists annually visit the Corn Palace, which is decorated inside and outside with murals made from about 275,000 ears of corn of various sizes and colors.

The upgrade includes the new domes as well as new lighting, larger murals, exhibit space, a theater and a walk-out balcony above the marquee. Work began in June 2014. Most of the work should be done this week.