The Palomar Ballroom burned to the ground on October 2, 1939. It claimed to be the largest dance hall on the West Coast, at 3rd Street and Vermont Avenue in Los Angeles. The swing era of jazz began there, according to http://www.laobserved.com/archive/2010/08/swing_era_of_jazz_began_a.php and other sites, with a performance by Benny Goodman and his band in 1935.
“From 1937 to 1962 [Peter B. Yates] was a functionary at the Calif. Dept. of Employment in Los Angeles, but this bureaucratic occupation did not preclude his activities as a musical catalyst. In 1939 he inaugurated on the rooftop of his house in the Silver Lake district of Los Angeles a chamber concert series which was to become an important cultural enterprise in subcultural Calif., under the name ‘Evenings on the Roof,’ he served as coordinator of these concerts from 1939 to 1954, when they were moved to a larger auditorium in downtown Los Angeles and became known as the ‘Monday Evening Concerts.’”
“The annual swallow migration has received a lot of attention over the years. For instance, Leon Rene’s 1939 hit, When the Swallows Come Back to Capistrano song lyrics are a tribute to the long migration.
“The amazing journey takes the swallows over 12,000 miles round-trip. They abandon their winter haven in Goya, Corrientes, Argentina and travel to southern California, arriving on St Joseph’s Day (March 19th)…”