This massive new development on Russky Island is one of Vladivostok's planned key attractions and opened with great fanfare in 2016. It's a vast space in a remote, purpose-built building, and while it has all the potential to be a great attraction, it actually had the feel of a place struggling on our last visit. The dolphinarium was closed, many tanks were empty and no food or drinks were available. Hopefully things will improve in time.
To get out here, jump on bus 15 from ul Aksakovskaya and get off at the last stop. A free shuttle bus will take you to the oceanarium's main entrance, or you can just walk the 500m yourself.