• Book online a day ahead, since tickets cost less online than at the door, but an online ticket is only valid on the day you booked
• Plan 1.5 to 2 hours for the full route; tickets last all day, so get a hand stamp if you step out and want back in
• No eating in the exhibits: bring snacks to eat in the Luoto or Submarine meeting rooms when no meeting is on

An indoor aquarium beside the Linnanmäki amusement park. The biggest tank holds 250,000 liters, with an underwater tunnel through it where blacktip reef sharks and snapper swim overhead. Other zones hold rays, a coral reef with clownfish, rainforest piranhas and seahorses.

Staff run feedings through the day, and at the Discovery Pool kids can touch sea urchins with staff. A small play corner by the ocean tank suits toddlers.