From the event planner:

I have an event that will interrupt the flow on the South Ship Canal Trail on Saturday, 10/21 from about 6pm to 7pm and the Mayor’s Film Office highly suggested I let the blog know.  We certainly don’t want to inconvenience/annoy anyone.

We are going to have a march from 1050 West Nickerson to 318 Nickerson (basically, the Fremont Bridge). This march may have as many as 200 people and will pretty much block the trail for that time (1 hour or less).