"Secure your cameras. Secure. Your. Cameras."
The guide walks up and down the boat as we wait at the base of Iguazu Falls, ready to go in and not only see the cascades up close, but feel their force – utterly. This is a trip that takes you, literally, into the pounding waterfalls.
Cameras are stuffed into supplied dry bags and waterproofs are hurriedly shoved on.
"Take them off," the guide says. Better to be wet and dry off quickly than sticky and sweaty in the high temperatures and humidity. And boy is it hot and humid.
The many falls look delicate from a distance and even as they tumble at speed, cascading into the river below, they don't look angry.
They are angry. That I had not expected.
As the boat rips and dips through the river and under the falls, the water hits me. I look up, hoping to get a view of the cascade from below.
Suddenly my ignorance is clear. I have to turn away and look down. It hurts. The force is simply too great. It smashes against my cheeks and my eyes. It really hurts.
Taking a journey with Nautical Adventures to go under the falls is one of the highlights of a trip to Iguazu, at least on the Argentinian side. The two-hour trek leaves from a building a five-minute walk from the Melia, the only hotel within the park itself.
Truck down to the river, take a short walk to the pier and off you go. It is well worth the expense of more-or-less $100.
On the Argentinian side, within the bounds of the Iguazu National Park, there are beautiful walks as well, paths that will take you to the many falls.
There are a number of circuits, most of which take about two hours and most are easy walks – flat boardwalks that are one-way, so it is impossible to get lost on the trails.
The one to the Devil's Throat ends at what looks like a giant well with megalitres of water pouring into its gullet every second.
Arguably the most beautiful is the upper circuit, dotted with stunning waterfalls that seem to go on forever.
Included in the price of the park entry ticket is access to an open train that will slowly and scenically take you from each of the major points. Be aware – too early and too late in the day, trains are very crowded and you may have to wait for the next one. Or the next. It can get very busy.
If you stay in Puerto Iguazu, the nearest city, there are the many amenities of a tourist town, but you will have to fork out the cost of transport to and from the National Park (entry is roughly $35, depending on the exchange rate at the time) which is likely to rack up at $US20 a pop each way for a taxi ride.
Staying at the Melia – the Sheraton until late 2017, when it changed hands – might be key to an easy trip. It is just metres from several of the major walks, and a stone's throw from one of the train stations.
LATAM and Qantas offer direct flights from Melbourne and Sydney to Santiago, Chile, and from there, connections are available through a number of airlines.
Air New Zealand has a non-stop flight from Auckland to Buenos Aires airnewzealand.com.au
The outfit based near the Visitor's Centre, Iguassu Falls Tour – Aventura Nautica, will take you on the boat journey. The rest is under your own steam although park guides can be organised locally, in a range of languages.
The writer travelled at her own expense.