A travel Blogger makes the trip and tells you all about it
"With the possible exception of holidays like Semana Santa, it is not necessary to buy a ticket well in advance – a day or two ahead of time will be just fine. The ticket office at the ferry terminal, located just south of the lighthouse at the inlet to Mazatlan harbor, is open seven days a week from 7 a.m. to 3 p.m. Both credit and debit cards are accepted and you will need either your original passport or a copy to buy tickets. The ship sails from Mazatlan on Monday, Wednesday and Friday at 5 p.m., and from La Paz to Mazatlan on Sunday, Tuesday, and Thursday (5 p.m. on Sunday, 8 p.m. on Tuesday and Thursday). The crossing takes about 12 hours."
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