Saw this on the local Denver news. Basically people were waiting around for buses to take them to the start line but the buses never showed up and the half marathon was cancelled. Sounds like a mess for all involved, it’ll be interesting to see the fallout on the cancellation i.e. refunds or not.
http://www.9news.com/story/news/2015/07/19/half-marathon-canceled-after-buses-dont-show-up/30388097/