Share this page: combined_logos_sequi-01.png Download the official Sesquicentennial logo: 150 logo Logo with Olympic City USA logo *Logos for editorial use only. Contact commdept@coloradosprings.gov for commercial use. COS 150 Tree Challenge: View more info on the tree challenge Download printable poster Additional Resources and History Official reading list Read an overview of the history of Colorado Springs Historic photos: Then and now