We visited the falls in 1999 traveling from Sao Paulo to Foz du Iguazu.
I can't wait to return since it was beyond amazing!!!
Our trip was cut short due to flooding in Sao Paulo which delayed our flight 10 hours and took a day of sightseeing from us . . . but we made the most of the one day we had by walking the paths on the Brazil side and then taking a taxi to Argentina.
Both sides have to be experienced.
My most vivid memory was arriving at the hotel in the middle of the night and hearing the roar of the falls prior to even seeing them. The sound is absolutely deafening.