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free aquarium

Some of the learning at the MaST Center is hands-on. (MaST Center photo)

MaST Center, a great free aquarium, reopens in Des Moines

The Highline College facility on Puget Sound is open to the public one day a week.

Originally published July 2021: Great news: The best little free aquarium you’ve probably never heard of is reopening for public visits!

The MaST Center (that’s Marine Science and Technology Center) is a working laboratory for Highline College in Des Moines. However, it is open for free Discovery Days, 10 a.m.-2 p.m. Saturdays.

It is literally on Puget Sound, located on a pier at Redondo Beach.

Inside the aquarium, there is 3,000 gallons of seawater, two large touch tanks and more than 250 native Puget Sound marine species.

The aquarium has marine mammal skeletons, including that of a 38-foot gray whale. There’s also a mesmerizing (in a bad way!) display of the plastic and other trash found in sealife stomachs.

Local art often is displayed, too, and educational displays explain current issues in the marine ecosystem of Puget Sound.

Divers from the MaST Center frequently go on collecting trips, so there is always something new to see at this great free aquarium.




While you’re at the aquarium:

Redondo is a big scuba-diving area, so there may be folks going into the water. There’s plenty of beach to explore, along with the half-mile-long Redondo Beach Boardwalk. Wooten Park nearby has a new play structure and lots of grass for running around, plus picnic tables if you’re ready for a snack or meal.

Sadly, the nearby Salty’s restaurant has not yet reopened, but we are keeping an eye on it! (But if you’re looking for a snack or lunch to have near the water, you’ll pass a Safeway and a couple of fast-food outlets between Interstate 5 and the Redondo area. Take the South 272nd Street exit.)

Seasonal only: Inspired to take to the water? Olympic Outdoor Center rents kayaks and paddleboards and sells a few drinks and snacks from its kiosk near the Redondo fishing pier.

More local aquariums:

Underwater fun awaits at Seattle Aquarium

Point Defiance Zoo & Aquarium in Tacoma



About the Author

Julie Hanson

Julie Hanson is a longtime journalist, South King County resident and mom to a 15-year-old girl.