What Do I Do With My Luggage?

Our flight isn't until 10:30 in the evening and we'd like to spend that day exploring Seattle, but are unsure what to do with our luggage. We don't want to carry it around with us. Has anyone had this experience and have suggestions?

thank you!

https://www.portseattle.org/page/cruise-guest-services-and-accessibility

Thank you! What a life saver that is going to be. All I could imagine was lugging my luggage all around Seattle for the day!