I have just arrived so I will update later. I talked to a lady on the bus about boats to Caye Calker and she said I could get one from Xcalak. This would be preferred option but I cand find anything on the net so it looks like Chetumal. I will let you know when I have sussed out some more.
for now I have got some ruins to go see at the beach .
Well I have sussed it out a bit more and I'm going to Chetumal on the bus tomorrow so I can cross the border into Belize at a regular border crossing so nothing goes wrong. There are fees to pay out of Mexico and into Belize. I think I can do that AND get ferry from there to Cay Calker.
I have checked out a bit more and th boat goes every second day so I will be in Chetumal for 2 days. Should give me enough time to get sorted then a few days lazing on a Carribean island. This holiday is lookin better all the time.
 
So today I went down to the ruins here at Tulum. Originally called Zama by the Maya it was changed to Tulum by the Spanish which means wall. You will know why when you see the pic of the Carribean coast from the site.