Sonic the Hedgehog 3. Bring blanket or low-back chairs. Food, local wine/beer, and non-alcoholic options sold. Lawn tickets: $6. Kids 12 & younger: free (ticket still required). Gates: 5 p.m. Weill Hall. Green Music Center. 1801 East Cotati Ave., Rohnert Park. Tickets: gmc.sonoma.edu.