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.