What better way for a junior ranger to spend their day than building a mini raft to race on spectacular San Francisco Bay. Join Ranger Heidi for mini raft craft building, learning about coastal navigation, and discovering how boats have been part of the Bay for centuries. Appropriate for all ages. No pets (except service dogs) are allowed. Park entrance fee waived for participants. Adverse weather or poor air quality may cancel; if in doubt, text or call (415) 302-1034 two hours before the event to confirm the status. Registration required.