It's that time of year when post office employees turn into Santa's elves, making sure all the holiday mail is delivered on time.

This month, Trip in Time looks back at the early days of East Bay mail from horse to plane.

Congress established the United States Postal Service in 1775. Eighty years later, on March 2, 1855, papers arrived from Washington, D.C., to Oakland Postmaster Thomas Gallagher at his saloon and grocery store at Second Street and Broadway, officially recognizing the Oakland Post Office.

In 1903, the city opened its first permanent post office building, a grand structure at Broadway and 17th Street. By 1914, the mail was being delivered by automobile fleet.

The first transcontinental airmail flight landed in San Francisco from New York in 1920, and soon planes were stopping in Oakland, Hayward and Concord.

Join us for a photo slideshow of these events and more at