We took an Alaskan cruise with Royal Caribbean last summer and we loved it. The ship got pretty close to the glaciers, food was excellent, and the highlight to me was the dog sledding. We took a helicopter to one of the glaciers, went on a dog sledding tour, then took the heli on an extended glacier tour. The pilot landed us on a nice spot and we explored the glacier on foot for awhile, then hopped back in the heli to take us back to the port.