Founded in 1912, Koyasan Beikoku Betsuin - aka Koyasan Buddhist Temple (342 E. 1st St, Los Angeles 90012) is one of the oldest existing Buddhist temples in the North American mainland. The temple is a branch of the Koyasan Shingon Buddhism and is the North American regional headquarters. Japanese art and religious objects, such as Buddha statues and stone lanterns, are displayed in the entryway. The altar inside the temple contains decorative objects of Buddhist symbols such as twin mandalas, scrolls and banners. Open daily to visitors, the temple hosts a wide range of weekly and monthly services, activities and cultural festivals. The temple is also home to Boy Scout Troop 379, which was formed in 1931 and is one of the oldest troops in California. Star Trek icon and gay rights activist George Takei was one of the troop's members.

In 1912, the temple established its first location in a storefront near Elysian Park. The temple was moved in 1920 to a larger building on Central Avenue. To commemorate the move, a tree was planted by temple members in front of the new building. Today it's known as the Aoyama Tree, a Little Tokyo landmark - the Japanese American National Museum stands at the temple's second location. The temple's third and current building was built on East 1st Street in 1940. Following the attack on Pearl Harbor a year later, the new temple was closed while its members were forcibly relocated to internment camps. During World War II, the temple was mostly used for storage space for internees. When it reopened in 1946, the temple had to rebuild its congregational base after families and residents of Little Tokyo were scattered outside Los Angeles.