The Jefferson Memorial is framed by blooming (开花的) cherry trees along the Tidal Basin in Washington, DC. Every spring, the cherry blossom is the most attractive site in Potomac Park. In 1912, the mayor (市长) of Tokyo, Yukio Ozaki, donated 3,000 cherry trees to the US in order to enhance (增进) the friendship between the two countries. Most of them were planted in the park. The cherry blossoms serve as a symbol of the coming of springtime, and a National Cherry Blossom Festival is held in DC every April, lasting two weeks and attracting more than 1.5 million visitors from all over the world.