Info from Wikipedia
Hy-Vee Arena, previously known as Kemper Arena, is an indoor arena located in Kansas City, Missouri. Prior to conversion to a youth sports and community gymnasium facility, Kemper Arena was previously a 19,500-seat professional sports arena.
It was originally named for Rufus Crosby Kemper Sr., a member of the powerful Kemper financial clan and who donated $3.2 million from his estate for the arena. In 2016, it was listed on the National Register of Historic Places in recognition of its revolutionary design by Helmut Jahn.