This evening a couple thousand children will participate in the annual Summerville-Trion Optimist Club Halloween Walk in downtown Summerville.  Local Optimist Club President Sandy Weaver says that parents or guardians can park anywhere and let their trick-or-treaters start anywhere in downtown Summerville.  Local merchants, civic clubs and churches will be set up all up and down Commerce Street to pass out candy.  Summerville Police will be on hand to help with the event.  Everyone is urged to use caution when crossing the street and to keep an eye out for children.  If you plan to travel through Summerville between  4PM and 6 PM, please use extra caution and watch out for pedestrians.