I've had multiple interesting experiences crossing international borders. Like the time I got food poisoning while crossing the border from Mongolia into Russia. Or the time I forgot I had a water gun in my luggage when flying out of Israel. But my time at the Chilean-Bolivian border must have been the most bizarre.
During the 4 day Uyuni tour, our tour group stopped at the Chilean-Bolivian border to drop off some group members who were continuing onto Chile.
Americans have to pay $150 for a visa into Chile, so I wasn't one of them.
The moment we arrived at the border, I was very surprised. Here is what the international border looked like:
It was just a single line in the sand. In the photo above, I'm in Chile and my Caribbean friend is in Bolivia. All you have to do it walk across the line in the sand, and you've crossed the border.
Of course, near the line-in-the-sand international border, there was a small blue building on the Bolivian side where stamps and visas are issued into Chile. The building also had a poll-bar that was open the entire time. Cars could freely pass as they wish.
A few yards away from the line-in-the-sand border, there was a "Welcome to Chile" sign on the Chilean side. My friend and I walked across and took photos. In Chile. Which is technically illegal, but nobody was enforcing anything and a bunch of white tourists were crossing it too.
So technically, I was in Chile! Even though it was only for a few minutes. And technically, illegally. But when the international border is just a line in the sand, then I guess nobody cares.