Fodor's Expert Review Oceanário de Lisboa
East of most of the city's sights in the sprawling Parque das Nações, Europe's largest indoor aquarium wows children and adults alike with a vast saltwater tank featuring a massive array of fish, including several types of shark. Along the way you pass through habitats representing the North Atlantic, Pacific, and Indian Oceans, where puffins and penguins dive into the water, sea otters roll and play, and tropical birds flit past you. You then descend to the bottom of the tank to watch rays float past gracefully and schools of silvery fish dart this way and that. To avoid the crowds, come during the week or early in the day.