DAY 114: When Lara and I signed up for a tour of the Argentine side of Iguazu Falls with the Hostelling International office, we spent the extra 10 real on a tour called "Gran Aventura" that included both a truck and boat ride. Like the Six Flags theme park with the English translation of the tour name, the tour included a wet and wild ride through the roaring rapids of the Rio Iguazu.

Seventeen of us from the Brazilian hostel -- most in their college years, born 1981 or later -- hopped on a bus clearly marked "TURISMO" on its side in huge letters. The driver, a happy Argentine man named João Paulo who joked about only letting girls on the bus and no guys. He drove us to a supermarket near the border, waving and honking at all the passers-by with the familiar "Shave and a haircut" melody, always completed by the other person with the "two bits" part.

After a brief but uneventful border crossing -- and one hour back in time with the time zones -- we were transported to Argentina. It was great to be back in a Spanish-speaking country where the signs looked familiar again.

João continued his "Shave and a Haircut" drive through the border town of Cataratas, to the point of the "tres fronteras" where one could see the national towers of Brazil, Paraguay and Argentina at the same time. From there we went to the entrance of the national park where we split up -- most in the group without the truck tour, and me, Lara and a Scotsman named Jaime in the "Great Adventure" one. Before the adventure started, Jaime and I visited the nearby museum where I learned about the poisonous black, red and yellow butterfly to avoid.

Lara, Jaime and I joined the handful of other and got aboard the 4x4 transport vehicle that took us on a relaxing drive throug the subtropical rainforest -- most of which was pretty boring unless palm trees excite you. After a 20-minute lack-of-animal safari, we arrived at Puerto Machcu, where we donned on life vests for the real adventure: a motorized raft ride up the Rio Iguazu. Unlike the "Roaring Rapids" ride at Six Flags' Great Adventure, all the drenching waterfalls were all powered by nature.

The captain took us up close to the San Martin, Mendea and Mbigua Falls for a photo opp and then up against the current of the river and under the Dos Mosqueteros Falls for a soak. Swinging around we went back to and under the tremendous San Martin Falls where nothing in the raft stayed dry unless it was in one of the plastic bags they had provided us with.

JAIME RAN OFF TO CATCH A FLIGHT and so it was just Lara and I who dried out on the rocks with a homemade sandwich picnic. Afterwards, we still had a good five hours to kill in the park and took a boat to the Isla San Martin -- supposedly the only island in the world surrounded by falls -- and trekked to an outlook point of the San Martin Falls. We trekked around the island -- on the way, Lara stopped for a "bush piss" in the woods and got startled by a rustling in the leaves (hoping it wasn't a ferocious quati); and we had a sighting of the poisonous butterfly I learned about that morning (we avoided it).

Back on the mainland of Argentina, we trekked up to the Bossetti Falls and stopped off at a sidewalk cafe to write some notes -- only to end up distracted and attacked by a swarm of bees invading anyone with a soda can. We took the mini-train to the far side of the park, where we saved the best for last: a catwalk that led to an observation deck overlooking the Devil's Throat (picture above), where millions of gallons of water spilled from higher to lower ground. We made our way through the pushy photographers and managed to take photos ourselves. Mist filled the canyon as a rainbow appeared out of thin air.

The trail we did afterwards wasn't nearly as impressive so we just rushed through it and head back towards the entrance as the day was getting late. Instead of taking the train back to the main station, we walked a short trail, stopping for photo moments along the way: one of Lara's Wari people dolls on the train tracks a la the 1986 movie Stand By Me, one with Lara doing a cartwheel; and one of me spinning around in a circle twelve times like a four-year-old until I was too dizzy to stand straight. (Why don't adults do this more often?)

We met up with the four British college girls from our hostel at the pizzeria in the food court and then went back to the TURISMO bus. It was easy to find when João did his signature "Shave and a Haircut" melody.

WE WAITED A GOOD FORTY MINUTES FOR THOSE WHO CAME LATE -- João psyched them out by driving away for a bit when they approached so we could see them run -- and then zoomed back over to Brazil and back to the future of one hour. We continued the festivities that night at the poolside bar with the rest of the big group that had gone to Argentina that day and some other newcomers to the hostel camp. Amongst the many rounds of drinks, Lara and I confirmed that most "cool" people were born before 1981, although there were a couple of exceptions on both sides.

The festivities went on all night and until morning for some -- all part of this complete Great Adventure.