Back to Honduras for a moment.
Much of Honduras is made of limestone. The roads are often carved through pure pockets of limestone. The local business take advantage of this in a unique way. They have polished the walls alongside of the road and covered the limestone in advertisments.
This sort of thing happens a lot in Central America but it usually consists of crudely painted slogans. Here the limestone allows the creation of advertisments that are works of art. They are able to paint in full color and the rock holds the colors like a canvas.