Known as OMSI, this hands-on science museum on the east bank of the Willamette River is particularly good for children. Hundreds of interactive exhibits across science, technology, and natural history; an IMAX/OMNIMAX theatre; and a decommissioned US Navy submarine (USS Blueback) moored alongside that can be toured. Open Tuesday through Sunday.
Oregon Museum of Science and Industry
Hands-on science museum with IMAX theater and a real submarine