Photo Gallery: Shots from the Sand at Nation's Largest Sandcastle Competition

The 31st Annual U.S. Open Sandcastle Competition and festivities connected with it brought hundreds of thousands of people to the most southwesterly city in the United States on Saturday and Sunday for what organizers say is the nation's largest sand castle competition.

Bands playing everything from reggae to rock kept the tempo high for the weekend, entertaining on the main stage in Pier Plaza, while roughly 150 vendors lined Seacoast Drive. 

A total 32 teams competed this year in amateur and master's categories, said Team Registration Coordinator Sherrill Pallotto. That's 10 fewer than last year, but she attributes the drop to a busy weekend in other parts of town, with opening weekend at the Del Mar Racetrack and Comic-Con in downtown San Diego.

International teams brought sand sculptors from Mexico, Italy and Japan to compete, but the majority of teams came from Imperial Beach and San Diego.

Among sculptures seen this year were Angry Birds and Transformers sculptures, and tributes to the NASA Space Shuttle, American Armed Forces and to the international community that assisted Japan in the wake of the earthquake and tsunami that devastated the island nation in March.

Bernie Miller, also known as Bern Dog the Surf Reporter, is a 51-year-old sand digger and spokesman for , a team that has participated in the sandcastle competition since 1988.

This year, their sculpture is "It's a Plane Crash Sand Castle," which depicts a plane crash that has cut trees down to their stumps.

"The window's broken and the pilot is stuck in the bank over there," he said. "The crash ripped his pants clean off."

Oddly, two Monopoly replicas were made in plots of sands next to each other. Both teams won first and second place for Best Replicas.

"I've been doing this for a long time and that's never happened before," Team Registration Coordinator Pallotto said. 

A total of $21,000 in prize money was handed out to top winners in five categories, including $5,000 to first place Masters A division winner I.B. Posse for its tribute to American armed forces. Last year the group won first place for "Got Oil," its depiction of the BP oil spill.

Teams were given five hours to make their sand castle or sculpture and only allowed to use simple hand tools, buckets and biodegradable or natural sea items such as seashells for decorations. Several teams could be seen using straws to delicately blow sand out of place to be as precise as possible.

Each had a 30-foot-by-30-foot plot of sand to act as the blank canvas for their work of art. Some, like Team Santa Barbara Sand, only used a few feet to create Beach Budda, but an eight-person team organized by Tsukamoto Masayoshi used all the space in their plot to spell out a simple message: 

"TO OUR FRIENDS AROUND THE WORLD, THANK U 4 UR SUPPORT FROM JAPAN."

In the corner was a miniature Mount Fuji.

"A lot of my family had to move because of the radiation, and especially there they got a lot of help from overseas," Masayoshi said.

Team Tensho was primarily made up of Japanese citizens currently working in the United States or Mexico with family in Japan.

Due to a miscalculation or mistaken reading of tide tables, water began to intrude on sand castles as early as 3:10 p.m. instead of 4 p.m. as was anticipated, she said.

Masters A Division

Masters B Division

Castles of Your Mind

Creatures of the Sea

Best Sculpture

Executive Sandbox

Best Replica

Cox Communications was the event's presenting sponsor.

Other sponsors included Foster Farms, Subway, Dyson, Vitamin Water, San Diego County Credit Union, Almond Accents, Ford Motors, Geico, California American Water, Verizon and Wade Entertainment, Scoreboard, Coronado Brewing Company, EDCO Disposal and New York Times Company, Z90.3 and Magic 92.5.