Boulevard Boo! Parade – 10 a.m. Saturday
El Cajon Boulevard from 59th Street to Aragon Drive.
Halloween Bah on the Bay – 1 to 5 p.m. Saturday
The event at Seaport Village features photos with a living scarecrow, a kids costume contest, scavenger hunt, monster mash band and carnival games throughout the day, according to organizers. www.seaportvillage.com
BOO BASH! – 1 to 4 p.m. Saturday
The Salvation Army Kroc Center Recreation 
Field at 6845 University Avenue will feature pumpkin decorating, carnival games and bounce houses. www.kroccenter.org
HAUNTED AQUARIUM: Shipwrecked! – 6 to 9 p.m. Saturday
At the Birch Aquarium, organizers invite you to enjoy close encounters of the fishy kind, BOO-gie down with Billy Lee and the Swamp Critters, and explore our wreckage for sunken treasures. www.aquarium.ucsd.edu
San Diego Monster Bash – 6 p.m. to midnight Saturday
Over 8 streets of the Gaslamp and East Village will be filled with thousands of party-goers, making it the largest Halloween event in California, according to organizers. www.sandiegomonsterbash.com
