This topic was posted as a question early this year and it seemed like a good bit to include in my trip this winter. Unfortunately it appears the post has been deleted as numerous HUBB searches have failed to find it recently. I don´t know who the original post was from nor can I remember the names of respondents.Before it disappeared the replies concluded that there were two crossings of the Rio Ucumacinta, at Frontera Corozal and Benemerito de las Americas , which both involved much struggle with getting on and off the small boats and up steap riverbanks-- possible but impractical. The third crosssing which was reported by another poster who had done it involved a land route southeast of Tenosique, Tabasco but left some unanswered questions.
From field research in the past week I can now affirm that the land route does indeed exist ...BUT... it is good for dry weather only as it consists of only a set of 4WD (?) ruts wandering about in the grass, rocks and topsoil between two fencerows. The Mexican road from Tenosique is good quality pavement 60km southeast out of town to the border crossing called El Ceibo, almost exactly in the 90 degree angle made by the border and on the south bank of the Rio San Pedro. .The Mexican customs post there is open 9 am to 5 pm , 7 days a week. The Guatemala side has NO customs post at the border . The Guatemalan paperwork must all be completed after traversing the 22km to the town of El Naranjo where there is the customs office in town. From El Naranjo the road is again excellent pavement of recent construction, connecting to pavement to Coban and Flores etc.
There are some 12 small inexpensive hotels in El Naranjo which do a good business serving a steady stream of illegal immigrants who can be seen diving off the road into the brush in Mexico as one approaches .Virtually all the traffic to the border in Guatemala is via launches on the Rio San Pedro, even some larger cargo boats capable of carrying 22 tons of sand exist, again a boat trip may be possible here too.
The scenic route from Palenque to this crossing , all pavement, consists of going south from Palenque on Mex 199, turn east onto Mex 307 , then at Rio Chancala turn north to Gregorio Mendez then Mex 203 east to Tenosique(hotels) and to the border at El Ceibo.Alternately ,take the short state route to Emiliano Zapata , off Mex 199 north of Palenque, and then mex 203 to Tenosique, etc.
The day I got to the border it had rained overnight and after bumping across the protruding bedrock and mud hill which passes for the main street I saw 500m outside of the Guatemalan village that NOOOO WAY was I going to even try getting my R1100GS on street tires through that mess. A minor detour involving a ride to Chetumal, then through Belize and west though Guatemala got me to El Naranjo anyway 3 days later.Investigation there showed that the mud track extends to within 3km of town before turning into rough gravel.
If only the entire road was like that .As it is now it would be best to wait at least two days after a rain to let the mud dry up some and the puddles to drain. It can rain here any day of the year.Off- road tires would be a definite asset, or group travel to dig one another out.
South of Tenosique there are two other small border road crossings, at the end of gravel roads at hamlets called San Francisco (east) and Corregidora Ortiz Neither has any form of customs for either country, gravel 7 dirt roades continue in Guatemala. One could ride dual purpose bikes in and out with no paperwork e.g. to see the archaeologic site of Piedras Negras.

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Great post Sjoerd! A little update to the info listed there. The road from El Ceibo to El Naranjo is perfect new pavement. There is still no customs on the Guate side. Mex has customs and immigration.

Thanks for reminding me and bringing this post to my attention again. I thought I had done a update on it but that was on the other site.
I did this border crossing from Mexico to Guatemala again this past March 2009 and also enjoyed the new pavement- so much that after spending the night in El Naranjo I went back to the El Ceibo border and then continued back into Guatemala and on to Panama and return.
There is only a partial customs service on the Guate side , as you discovered. There is only a Migracion for Guatemala agent, but no SAT office to do the temp import for the bike or car. This can create problems for the traveller who wants to go farther in CA to Honduras , as I discovered.
If you are going to visist ONLY Guatemala it is not such a big issue as you will be heading back out to Mexico or Belize and can arrange the temp import at one of the inland SAT offices or at the border just before leaving, if they are raising a stink that you should have it. Or leave GT by the same EL Ceibo crossing.
I found out at the Aguacaliente crossing to Honduras that the woman in charge of the SAT office was stuborn and adamant in not allowing my bike out of GT without me going back to the Mexican frontier to get that paperwork done.
To get around this problem I suggest that other travellers with the same dilemma do as I did: go to the Florido Copan crossing into Honduras. The officials there are much more understanding and flexible as they deal with a regular stream of tourists. They WILL let you exit Guatemala if you explain clearly why you could not obtain a temp import permit at El Ceibo.They will even issue you that document if you want, but save your money and do it on the return leg of the trip if that is your route plan.
As the road from El Ceibo is still brand new it is to be hoped that Guatemala will soon install a full service border processing office there . Hours of service are currently only from 9 to 5 but as more commercial traffic builds and the route becomes popular that may be expanded.
We could all drop an e-mail to the Guatamala tourist department suggesting that they upgrade their tourist border crossinbg service at El Ceibo.

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