We visited the Lisbon Zoo in large for our 2-year old, as part of a 3-week trip to Portugal. We were extremely impressed!! The zoo is in a fantastic condition & the grounds are extremely beautiful and have lots of shade and beautiful vegetation. Walking through the zoo is a pleasure and you hardly feel the time go by. There are lots of different wild animals - bears, lions, monkeys, giraffes, etc., as well a as a wide variety of birds. The zoo also has a small ocenarium with 2 dolphin shows during the day (the second one is at 3 pm & unfortunately I don't know the time of the first one).
The zoo also has a kiddie train that takes you through most of the zoo and offers commentary throughout (only in Portuguese). It costs 1 Euro per person and is definitely worth it for the little ones. There was also a separate amusement park area, again catering to young children. However, it was closed on our visit there and seems to only be open on the week-ends during the fall.
The zoo is usually not something you visit while exploring a new country; however, I cannot recommend it enough, especially if you are traveling with little ones.
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