iMore

Is there a way to consolidate all my calendars into one? It appears I have several calendars with entries on one calendar but not another and some entries on multiple calendars. I just need one but I don't want to have to go through the process of sifting through each month and moving entries into one manually. Currently, my banner on my iPhone shows the same event 3 or even 4 times. Kinda annoying. Can anyone offer any suggestions?