Visit Pella is the local tourism bureau in Pella, and while there’s been a fair amount of people coming to the Tulip City this summer, some of the biggest days for tourism locally are starting this week. Director Ann Frost anticipates big crowds as race fans from around the world come to the 62nd NOS Energy Drink Knoxville Nationals through next weekend. Frost says many fans choose to make their week long stay in Pella and others come for a day or two during their Nationals experience.