Public Transportation options from Des Moines International Airport:  Note that cabs serve any location in central Iowa, while buses serve  throughout the Metro area. 
The Executive Express shuttle service has a booth in the baggage claim area, providing service to Ames and other Iowa cities.

Iowa State University (ISU)
  at 2501 N.Loop Drive, Ames, IA 50321:  (if driving go north to I-80; east on 163 & north on I35; exit at SR 30 with a short drive west to Ames. The 40.6 mile distance takes about 48 mins (without traffic). For transportation options to ISU, open its website.

Des Moines Area Regional Transit 'DART' public Bus Route 8 serves the Airport. (tel. 515-283-8100 - for route map open: & schedule open http://www.ridedart.com/bus-schedulesroute-map.cfm).
Heart of Iowa Regional Transit Agency 'HIRTA' (tel. 877-686-0029  or visit:  www.ridehirta.com) is an interstate transit bus line linking Central Iowa and the surrounding counties around Polk (where the Airport & the City of Des Moines are)

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