It took over an hour from the time I checked in for the excursion, to the time I got to the Atlantis (and note that it is only about a 5-10 minute bus ride from the ship to the Atlantis). They had us waiting on the ship before taking us off, then they had us waiting next to the ship before they took us into the port, and then they had us waiting in line to board busses to get to the Atlantis (we literally felt like cattle). However, once we arrived to the Atlantis, I had an unbelievable time. The water park is a ton of fun, they provided a meal voucher for lunch, and they had busses departing back to the ship every 30 minutes starting at 1pm (and there wasn't any line for the return trip bus). I would recommend the excursion to the Atlantis, but would warn you that you'll be doing A LOT of waiting around before you get there.