I've almost been there. In fact from a technical point of view, maybe I have?
We've stood at the corner of Argentina and Brazil, where we could see Paraguay, waving to us from the opposite shore.
We've been on a boat ride along the Paraná River, and we definitely crossed the midpoint, but we didn't touch the opposite shore. So we were in Paraguayan waters.
And the most objective evidence? Naturally, I picked up a cell phone signal and got the message, 'Welcome to Paraguay! Your T-mobile plan gives you..."
So, have I been there? I didn't put a star on my map. But, awfully close!
Great journalism. Hook the audience with a stunner in the first line, and they can't stop reading until the question is resolved!