The world has a lot of - so called - 'tripoints'. It's the point where the border of 3 country's meet each other.

China is the country that has worldewide the most tripoints: 16. In Europe, Austria is the country with the most tripoints: 9 in total.

For an overview in Europe; click [here].

Right of this text, I displayed the tripoints I've visited. They link to a photopage.

Click on the image for the interactive website of Jan. S. Krogh.
You also can click [here] for a wikipedia list.