The Hatfield Marine Science Center is the public-facing wing of Oregon State University's marine research operation on Yaquina Bay. It is smaller and quieter than the Oregon Coast Aquarium next door, and it has a different mission: to show you the science, not the spectacle.
The Visitor Center has touch tanks, real research equipment, and live displays explaining ocean currents, plate tectonics, and the local fisheries. A giant Pacific octopus often dominates one corner. The Center is free (donations suggested), open most days, and pairs well with the aquarium if you have a curious teenager.