Deadweird is usually a two day celebration. Generally, it is held the Friday and Saturday closest to October 31st. And, the big costume contest is held on the Saturday night.
This it definitely one of the popular Deadwood Events. You just never know what you will see.
2016 October 28th and 29th
2015 October 31st
October 31st and November 1st 2014
October 26th and 27th 2012
October 25th and 26th 2013
Visit the Deadwood Chamber of Commerce Website for the full schedule of events.