We stayed at the Hilton downtown and then Urbered to the Port of Miami. Your departure documents will tell you what pier (A-F) to tell the driver.
I would recommend you stay somewhere near the pier, but as long as you're in Miami and take all the precautions, then you should be fine. They require you to check-in 90 minutes before departure, so make sure you plan ahead of time and give yourself extra time to make it to the pier in case of any possible delay. The address is 1050 Caribbean Way. As your vacation approaches, Royal will e-mail you any and all information you need.
The Royal Caribbean use Miami dock A. That's the address that Uber used to drop me off and pick me up. There are plenty of places to stay. I stayed downtown. It is close to South Beach and the after hours clubs. I suggest riding do not walk between the two areas.
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