Photo taken on Oct. 26, 2019 shows sandcastles made by competitors during a sandcastle competition in San Francisco, the United States. The annual Leap Sandcastle Classic brings thousands of people to San Francisco's Ocean Beach every year to build super-sized sand sculptures. (Photos: Li Jianguo/Xinhua)

Photo taken on Oct. 26, 2019 shows a sandcastle made by competitors during a sandcastle competition in San Francisco, the United States. The annual Leap Sandcastle Classic brings thousands of people to San Francisco's Ocean Beach every year to build super-sized sand sculptures.

Photo taken on Oct. 26, 2019 shows sandcastles made by competitors during a sandcastle competition in San Francisco, the United States. The annual Leap Sandcastle Classic brings thousands of people to San Francisco's Ocean Beach every year to build super-sized sand sculptures.

Photo taken on Oct. 26, 2019 shows sandcastles made by competitors during a sandcastle competition in San Francisco, the United States. The annual Leap Sandcastle Classic brings thousands of people to San Francisco's Ocean Beach every year to build super-sized sand sculptures.

Photo taken on Oct. 26, 2019 shows sandcastles made by competitors during a sandcastle competition in San Francisco, the United States. The annual Leap Sandcastle Classic brings thousands of people to San Francisco's Ocean Beach every year to build super-sized sand sculptures.