Between 1926 and 1932, local, state and federal authorities in San Francisco; Oakland; California; and Washington, D.C., leaned in to an intense process for determining how best to create a transbay vehicular and rail bridge linking Oakland and San Francisco.

There were at least four major studies focusing solely on the bridge issue or, in one case, the bridge as part of broader regional transportation concerns.

Three of these studies — in 1926, 1927, and 1930 — included the specific location and route that Emperor Norton backed in 1872: Oakland to San Francisco via Goat Island, with a San Francisco landing at Telegraph Hill.

All three of these studies shortlisted two options that, between them, included these features: (1) direct connections between the traffic centers of Oakland and San Francisco; (2) a “hinge” at Goat Island (Yerba Buena Island); and (3) a San Francisco landing at Rincon Hill.

The 1930 study was the first to include an option that put all these features into one location and route — the one that eventually was built.

Read on for the Big Picture story of how it all came together — including the top-line maps, produced for these studies at the time, that illustrate the evolution of the design of the Emperor Norton Bridge.