The majority of the falls are on the Argentine side and this side provides the more up-close and personal experience. There are more than 270 falls in an area where cliffs and islets are scattered in a half moon. The Argentine side options are more scattered and take longer to see and there is even a train to help you get around.
All visitors enter the falls area through the visitors centre. This is the location of the La Selva restaurant, toilets and a range of other facilities. From the visitors center you can walk along the Green Trail or catch a picturesque train. Both take you to Cataratas station. Along the way you will see butterflies, birds and coatis. From here a trail leads to two basic circuits: an upper path and a lower path.
I recommend that you start with the upper circuit (Circuito Superior). This is the least spectacular but is easy walking and it builds anticipation. The trail is 1200 metres long and it crosses several arms of the river to provide views of several falls.
The lower circuit (Circuito Inferior) is a 1.5 kilometre loop which leads to the base of the falls. There are quite a few steps but it is a unique experience well worth the effort. As part of this circuit, one track takes you to the main river where you can take a free boat to Isla San Martín. This operates about every 15 minutes. On the island there are more trails and more close-up views. By now you will be wet!
Probably the best part of a visit here is walking to the top of Devil’s Throat. You leave on the train from Cataratas station and travel through the jungle to Garganta del Diablo station. Here a boardwalk begins at a point upstream of the falls and you walk past some tranquil islands before reaching the balcony on the Devil's Throat, the biggest of the falls with such a big flow of water that you will be overcome by the grandeur of the spectacle. The falls roar in your ears, the mist washes over your face and the rainbow arcs across the rush. It is a multisensory experience that will impress everyone.
There are a couple of places to find snack bars and you could always eat at the Sheraton Hotel. The light is best for photographs from this side of the falls in the late afternoon. Allow a minimum of four hours to enjoy this area.