Do NOT book your Catalina Express through Viator. The website doesn't alert you that the boats are full. They let you go ahead and book and pay for travel even though there is NO availability on the day/time you need. Then, when I asked for a refund at 9am the day before I wanted to travel, they inform me that to be refunded, I have to call 24 hours prior to travel. Well, I was calling the day before, I couldn't book a travel time because your website doesn't allow it, and there were NO SPOTS LEFT TO RETURN FROM THE ISLAND! I'm still waiting to see if they'll refund me my money. For some reason, they said it can take up to 72 hours for a response. That's AFTER I spent almost 45 minutes on hold while they (a) spoke to a supervisor and(b) called Catalina Express to confirm that I wasn't lying about the lack of availability on the return trips. They just want your money. Then, they'll figure out if they can actually accommodate your needs.