The 50 degree latitude intersects with the 6 degree longitude here near Luxembourg and is an example of the projects sites.  There is a marker at the spot.

Degree Confluence Project

The Degree Confluence Project is a World Wide Web-based all-volunteer project which aims to have people visit each of the integer degree intersections of latitude and longitude on Earth, posting photographs and a narrative of each visit online. Intersections are defined on the horizontal datum WGS 84. The project describes itself as "an organized sampling of the world".

• http://en.wikipedia.org/wiki/Degree Confluence Project