Throughout Mexico "topes," or speed bumps, are ubiquitous. These can be metal pods arrayed across the road, or asphalt humps, or even significant concrete wedges. You really do have to slow down, and almost stop to crawl over them. There is usually a sign warning they are ahead, because if you hit one going fast you can total your car. In other words, the topes are effective. Small towns will have one coming and going, because they are more effective than speed limit signs, which everyone would ignore. But even highways have them, near intersections or bus stops.
Along the southern coast of the Yucatan, beyond the last electricity and asphalt, at the end of the road, the Mexicans still want the benefit of a tope, but what to do on an unpaved mud/sand road? Well along the coast, where old ship ropes can be found, the solution is to lay a big fat rope across the road. It works, at least for a while, but it is easily replaced.
This one is strung across the road in the small pirate town of Xcalak, Yucatan.