Multnomah Falls is one of the most well-known, famous hikes in the Portland area. The hike is 2.4 miles total so it's a great day hike. You do need to buy a permit to do the hike, so this hike is something to plan ahead of time.
The Portland Saturday Market is nationally recognized as the largest open-air arts and crafts market in the country and rests right on the beautiful Willamette River.
If you want to get outdoors while visiting and are willing to make the ~45 minute drive, Mt. Hood has a nearly unlimited amount of hikes and lakes you can explore. There is also summer skiing at Timberline resort for the overly adventurous.
OMSI is a great museum to explore various exhibits both ones that are shown year-round as well as exclusive ones changing throughout the year.
This classic EDM concert venue is the groom's recommended place for those looking to catch a show while in town. The groom is happy to provide other music venue recommendations upon request as well!