Our cruise on the Celebrity Solstice sailed from Pier 91 in Seattle. Pier 91 is a couple of miles northwest of the Space Needle. We took a town car to the pier. The Solstice staff grabbed our luggage (with tags) and quickly disappeared. We were had Aqua Class passage so we skipped the long lines and were aboard the Solstice in 15 minutes.
There is a wonderful view of the Seattle skyline and Puget Sound from atop the cruise ship.