SAN DIEGO -- More than 750,000 people are expected to line the San Diego Bay Saturday night to witness the "Big Bay Boom," the largest Fourth of July fireworks spectacle in the region.

The annual pyrotechnics show put on by the Port of San Diego features fireworks shot simultaneously from four barges to live music broadcasts.

The best places to view the nearly 20-minute-long fireworks show, according to organizers, is from Shelter Island, Harbor Island, North Embarcadero, Seaport Village and Coronado Ferry Landing.

During the day, parades and Independence Day carnivals are planned around San Diego County, before fireworks light up the night sky at about a dozen locations in the region.

The annual "Spirit of the Fourth" festival is being held in Rancho Bernardo, featuring a pancake breakfast, entertainment, military displays, a parade, car show and fireworks.

There will be Fourth of July parades in Scripps Ranch and Mira Mesa with marching bands, firefighters and a color guard. A fireworks display is planned in Mira Mesa once the sun goes down.

At the San Diego County Fair, which concludes Sunday, there will be a "Hometown Heroes" parade, a performance by Smokey Robinson and a 9 p.m. fireworks spectacle.

In Carlsbad, Legoland California will hold its annual "Red, White and Boom!" Fourth of July celebration with games, entertainment and fireworks.

"As American as Apple Pie" will be the theme of a Fourth of July parade in Julian. The parade will feature horses, antique cars, and appearances by Miss Julian, belly dancers, drill teams and marching bands.

El Cajon will hold its annual Fourth of July picnic and fireworks show at Kennedy Park and an Independence Day carnival will conclude with fireworks at National City's Kimball Park.

At night, tens of thousands of people will line the shores of Mission Bay for two separate fireworks shows being put on by SeaWorld and the Mission Bay Yacht Club.

Independence Day fireworks are also scheduled at La Jolla Cove and off the end of the Ocean Beach Pier. The annual fireworks in Oceanside and Chula Vista were canceled this year due to limited funding.

Here's a rundown of public displays: -- SeaWorld, 9:30 p.m. tonight and Sunday, "Shamu's SkySplash USA," featuring fireworks set to patriotic music. SeaWorld San Diego, 500 SeaWorld Drive. Viewing also available along Crown Point. -- San Diego Big Bay Boom, 9 p.m. Fireworks will be shot simultaneously from four barges. Watch from Seaport Village, Harbor Island, North Embarcadero and Shelter Island.

-- Embarcadero Marina Park South, 9 p.m., preceded by a 7:30 p.m. Star- Spangled Pops concert directed by Marvin Hamlisch. Tickets, $15-$75; (619) 235- 0804 or sandiegosymphony.com.

-- Coronado, 9 p.m. Fireworks are staged over Glorietta Bay. -- La Jolla Cove, 9 p.m. View the fireworks along Coast Boulevard from Scripps Park or La Jolla Shores Beach. -- Lake Murray, 9:15 p.m. Lake Murray Community Park, 7001 Murray Park Drive in San Carlos. -- Mira Mesa, 9 p.m. Mira Mesa Community Park & Gil Johnson Recreation Center, 8575 New Salem St. -- Mission Bay Yacht Club, 9 p.m. Open to members only, but viewing is possible along the edge of the bay. 1215 El Carmel Place. -- Ocean Beach Pier, 9 p.m. The 30th anniversary fireworks show will be off Newport Avenue and Abbott Street. -- El Cajon, 9 p.m. Kennedy Park, 1675 East Madison Avenue. -- Santee, 9 p.m. Town Center Community Park ballfields, 9400 Cuyamaca St. -- Spring Valley, 9 p.m. Swap Meet parking lot at 6377 Quarry Road. View from Spring Valley Park, 8735 Jamacha Blvd. -- Legoland, 8:30 p.m. Nonpark guests are welcome to view fireworks from the parking lot for $2 after 7 p.m. 1 Legoland Drive. -- Del Mar, 9 p.m. The San Diego County Fair at the Del Mar Fairgrounds. -- Escondido, 9 p.m. Grape Day Park, 321 N. Broadway. -- Fallbrook, 9 p.m. The Grand Tradition, 1602 S. Mission Road. $10 to $35; (760) 451-3282 or fallbrookbeautification.org. -- Poway, 9 p.m. at Poway High School Stadium, 15500 Espola Road. Tickets are $2, free for children 10 and younger. Parking and shuttle service from 6 to 10 p.m. at nearby Lake Poway, 14644 Lake Poway Road. -- Ramona, 9 p.m. at Olive Peirce Middle School, 1521 Hanson Lane. -- Rancho Bernardo, 9 p.m. at Bernardo Heights Middle School, 12990 Paseo Lucido. -- National City, 9 p.m. at Kimball Park, 1249 A Ave.