The marker in Boulevard du Jardin-Exotique is located in the northwestern corner of Monaco, near Princess Grace Hospital. According to the excisting tourist maps the boundary column is standing very close to where the border is drawn on these maps. The France - Monaco border is at this point crossing the street towards the Monaco entry signs.

Photos of the column from three different angles. (Click to get up a high-resolution image.)

On this photo we see that the side walk surface changes a couple of metres before the border column.

Image towards south and France.

From about the same point as the photo above, but towards Monaco. Road D6307 is a French road number.  French road codes are not used in Monaco.

The position of this marker is at the "FRMC2" needle.  Google Earth's international boundary was in October 2011 not correct at this point.