This was our main destination for this 2-day trip into Seattle and was worth it. The cost was $20/adult was free for kids under 4 years old. Westlake Center link rail terminal was only three blocks down the pier so it was a nice walk. The only thing you might find a little stressful is getting down to Alaska Way from the Pike Public Market. Those with strollers will want to go in through the third pink entrance in the market to get to the skybridge. At the end is an elevator to the street level parking lot, which let's you get on to Alaska Way. We were impressed with the Aquarium because it was situated right on the pier and used the waters from Puget Sound for many of the actual exhibits. The sea and river otters were our favorites. The underwater cavern was a close second.