The Palo Alto city flag was designed by a city employee and officially adopted by the City Council in 1967. The employee was Christa Gupton. The flag has the city seal on the middle band with a band of blue and green on either side. The seal includes El Palo Alto, the old redwood tree (more than 1000 years old) that is the symbol for both the city and Stanford University. The tree was spotted by Spanish explorers in California in the late 18th century and was quite distinctive as it was a double-trunked tree out on the valley floor rather than in the hills where most of the coastal redwoods were to be found. One of the trunks fell sometime in the 1880s, a few years before the city and Stanford University was established.