This is La Paz, Mexico. Steinbeck came here with his marine biologist buddy,
Ed Ricketts, during the sea journey chronicled in The Sea of Cortez.
 

“Late at night we sat on the deck.
They were pumping water out of the hold of the trading boat,
preparing her to float and flounder away to Guaymas for more merchandise.
But La Paz was asleep; not a soul moved in the streets. The tide turned and swung us around, and in the channel the ebbing tide whispered against our hull and we heard the dogs of La Paz barking in the night.“
– John Steinbeck, Sea of Cortez, p. 126, (1941)

The character of “Doc” in Cannery Row was based upon Ed Ricketts.