You can no longer obtain visas for Mauritania at the border, it seems the income stream from this wasn't being passed up the line to the big bosses.

If you haven't organised this before leaving home, the only option in Morocco is to attend the Mauritanian Embassy in Rabat (7, Rue Thami Lamdaouar, Souissi, Rabat. Tel +212 37759125, GPS N33 58.838 W006 49.839). The following notes are provided by Tim Skilton of Locoformotos.

The waypoint above is for the doorway where you queue. Open 09.00 to 15.00. Now a '24 hour' service, submit at 09.00 come back at 14.00 next day. You need two passport photos, one copy of your passport, only one form, I had two of everything and he looked at me like I was some kind of idiot!

Polite, efficient service from a well-dressed gentleman. Passport retained for the duration of the process, so bear in mind if you will book a hotel in Rabat (need passport or copy). Cost for double entry (Morocco/ Mauritania, Senegal/ Mauritania, 510 Moroccan Dirhams.

I was there at 08.00. Door opens 08.30 and the fiches are distributed and also a piece of paper with your number on. Queue on right of the door as you look at it from the street. They get a bit shirty about this! You go in one at a time (according to your number) just through the metal door into small room. Same guy behind the counter. Polite and business-like. Takes completed fiche, two passport photos and copy of passport. Relieves you of Dirhams. Gives a receipt for your documents and passport, which are retained. "Come back tomorrow at 14.00"