on special occasions, certain parts of the arc that are usually open to all guests are reserved. campus recreation makes its facilities available to schools, departments, community groups, and organizations for virtually any type of event. for example, career fairs often use at least one whole gymnasium, causing those facilities to be closed for set-up the day before and used for the events the following days. although career fairs are usually hosted by certain colleges within the university, such as the college of business and college of engineering, all university of illinois students are allowed to attend them. other community events such as the christie clinic illinois marathon also reserve a gymnasium for participants to collect race information and materials.