San Juan, Puerto Rico
Other than the fact that the tour ran 2.5 hours late (due to a mechanical failure) and was hosted by a fill-in tour guide, we enjoyed ourselves. Unfortunately, the timing was such that we were unable to take the afternoon trip that we had planned, and were forced to go home with an item on our bucket list left incomplete. Requests for a partial refund have been ignored. And no apology was ever offered by Viator, which I find inexcusable. I would have expected better customer service.