Bainbridge Island is a fun excursion taking the Ferry from downtown Seattle across the Puget Sound. There are tons of shops, restaurants and activities (such as biking, kayaking , etc.) to do. All you need is a ferry ticket and some good walking shoes to explore the island as it is extremely walkable.
Pike Place Market is one of the most iconic Seattle tourist spots. It is a fun market downtown near the waterfront. You can spend hours looking at different foods/crafts, grabbing local foods and hanging out. We would recommend not parking within a few blocks of the actual market because traffic gets extremely condensed near the entrance. Street parking is ideal but there is plenty of ramp parking options.
The Space Needle is another iconic spot in the Seattle City Center. Tickets are usually $30+ per person and you see great views of the city and the Puget Sound!
If you find yourself on the waterfront, check out the ferris wheel! It offers great view of the city and the Puget Sound.
For a nice walk around some of the most beautiful spaces in Seattle, the Arboretum is a great way to spend the morning with a cup of coffee in hand.
The Seattle Art Museum is located in the heart of Downtown Seattle and boasts several well known collections and temporary exhibitions. A great activity in the Seattle rain.
The Ballard Locks is an awesome sightseeing feature just north of Seattle city center. It has many local restaurants and places to see views of the Seattle and the Puget Sound such as Golden Gardens Park.
Alki Beach Park is a long beach strip that runs roughly from 64th Place SW to Duwamish Head on Elliott Bay. It's a great spot for a bite to eat or a long walk any time of year.