Traveling West on The Old Spanish Trail Highway
Alabama: From the border with Florida to Mississippi
Alabama and Mississippi form a rather short part of the total highway mileage. But they were difficult sections of the highway to deal with. By the time the road was dedicated in 1929, drivers still had to take a ferry across Mobile Bay (the Bankhead Tunnel would not be completed until the mid-30s) and Mississippi finally had to build toll bridges across the Pearl and other rivers.
The people who made the 1926 Autotrails and Commercial Survey of the United States atlas marked roads only within the state's borders for each state; so the red line above does not mean the road ends at the two borders of Alabama. But do notice that the red line indicating the OST Highway ends abruptly at Daphne, Alabama, and then picks up again across the bay in Mobile. Intrepid travelers on the road until the 1930s would load their cars onto a ferry that would complete their trip across the bay to Mobile. The Appalachicola and Escambia rivers had been bridged, but Mobile Bay was a challenge that would have to wait for some years after the completion of the highway for Alabama to complete the tunnel that would be named the Bankhead tunnel.
OST through the old city of Mobile runs through some beautiful neighborhoods and, heading out of the city, travelers can now stop for a few hours to enjoy the beauty of the gardens at Bellingrath before driving on to the Mississippi coastal highway. The 1930 Gulf Oil Alabama State Map contains a not very detailed map of the city of Mobile that does show the route from what would have been the ferry landing on the Mobile River at Dauphin Street and then through the city.
If you look closely at the entrance to the Mobile River from the bay, you can see the dotted line indicating the route ferries took from the east bay at Daphne to Dauphin Street in Mobile. From Dauphin Street, travelers would turn south on Conception to Government Road then, after a few miles, left onto Fulton Rd. which turns slightly to the right to Halls Mill Rd. and, after crossing Eslara Creek, drive west to the State of Mississippi.