Since this question comes up a lot this time of year, and there have been a few incidents related to it recently, here's the latest info:
Parks Which Allow Night Riding:
--Bluff View (aka Zombie, dirt connector and paved Rock Hollow NOT Al Foster) (until 10pm)
--Lost Valley (until 10pm)
--Riding is also permitted on the roads at the Busch Wildlife Area.
--In St.Charles County Parks, unless it is part of one of the night rides organized by the Parks Dept., riding is permitted only until 30 minutes after sunset.