We decided to take this cruise even though we knew it would be extremely hot in July. The attraction was the itinerary, which for some reason is offerred only a few times this year.
We took the train from FCO to Civitaveccia. The first time we did that it was somewhat intimidating, but we have done it enough now that it is pretty routine. The last time we learned that if you change at Trastevere instead of Termini it is a bit less expensive and much easier to go to the platform for the next train (no long walk like at Termini, just two platforms here). July and August are when Italians go to the beach and the train was absolutely packed, so we had to stand in the boarding area near the doors, which was not air conditioned. This had not been the case when we have done this other times in the year. We were really glad to arrive at Civita, walked to the cruise port and took the shuttle bus to the ship.
Mariner is in fine shape and we found the cabin, food, staff, and entertainment to be excellent, as usual. With this cruise we became Diamond level Crown and Anchor Society members, so we have sailed with RCI quite a bit.