Prior to 2000 the convention was known as Nan Desu Kon . Renovations in the hotel were still underway prior to the start in 2003 , but did not affect the convention . The convention chose not to move to the Colorado Convention Center due to attendee logistic issues ( hotels , money , and parking ) . The convention instituted an attendance cap of 7,500 per day in 2011 due to event quality and attendee comfort concerns . The attendance cap of 7,500 per day continued into 2012 and the convention was a sellout . The convention added the Hilton Garden Inn DTC hotel in 2013 , occurred during the 2013 Colorado floods , and attendance remained capped at 7,500 attendees . Along with the flooding the fire alarm went off , tornado warnings occurred , long lines occurred , and the masquerade had to be stopped due to a medical emergency . The convention also hosted the World Cosplay Summit Mountain Qualifiers with Green Jello Cosplay winning
2013 Colorado floods
2013 Colorado floods
Nan Desu Kan