After the Boston Marathon bombing last year, the Boston Athletic Association is not taking any chances, banning a wide range of items from this year's race. 
 
Official participants are not allowed to have bags at all, personal hydration systems like CamelBaks are prohibited, and any container capable of carrying more than one liter of liquid is also not allowed. Just to name a few. (Via Boston Athletic Association)
 
But along with some of the practical things a runner might want, the BAA has taken a little fun out of its marathon. No costumes will be allowed, nor anything that covers a runner's face. (Via Twitter / @Milnes123 / @itvnews / @EnjoyTheViewEU)
 
Spectators will also feel the security overhaul. While bags haven't been outlawed for people coming to watch, those bags will be subject to search at any time. 
 
"We know it's intrusive but unfortunately in this day and age, it's a necessary evil." (Via WBZ-TV)
 
"We don't enjoy searching anybody but if the safety of the public is in danger they're gonna be subject to it." (Via WHDH)
 
Now along with all the "do not's" there are a few things that will be allowed on the track. 
 
Fanny packs are OK for runners, fuel belts are fine as long as the bottle is less than one liter and headphones are allowed on the track. 
 
Runners who want to have clothes to change into when they finish can drop them off before the race and they will be kept in clear bags about half a mile after the finish line. (Via WCVB)
 
But according to the Boston Globe, those involved in the race "seemed more concerned with traffic and potential damage to grassy walkways than they did about security."
 
The Boston Marathon is expecting record numbers this year — more than 36,000 runners compared to last year's 27,000 and at least 1 million spectators lining the streets to watch. (Via Flickr / Kinchan1)