My wife & I love animals, and as a biological scientist, I was already enamoured with the sheer biodiversity of plant life in Missiones. But animals are the cuddly charisma of the rainforest, and this is the best place to see them. You don't have to feel guiltly about going to a zoo with trapped animals because Guira Oga is doing good wholesome work as a rehab and breeding centre. The tour guides have a passionate knowledge of the animals and the rehabs work, and this is a prime place if you have come to Puerto Iguazu for the waterfalls but feel there is more...and this is especially a place to come if you have kids. Kids can get bored watching water fall, amazing as it is. But to see a howler monkey whooping up a storm is just plain fun. It is a little bit out of the city, and as my wife and I discovered, walking distance, but kind of a marathon walking distance. It's more recommended to get a taxi or remise, who you can arrange to pick you up after the tour. Overall: great place, great people, great work.