Las Mercedes (L-289-LM) is a complex archaeological site located on the Caribbean slope of Costa Rica between the foothills of Turrialba Volcano and the alluvial plain.
The site contains a variety of architectural features including platforms, plazas, retaining walls or terraces, funerary areas, ramps, and paved roads.
We know that the former inhabitants of Las Mercedes were still living there at the time of the initial Spanish arrival because a number of glass beads of historic European origin have been found during excavations.
[3] All of these platforms, circular or not, are thought to have been covered with conical shaped huts made out of organic materials that have decomposed without a trace.
[11] In the area near the stream Santa Emilia a footpath with a width of 3 meters was defined by a linear depression in the land’s surface.
[12] Both the Iroquois and Pocora causeways offered formalized, controlled, and ceremonial access to the central part of Las Mercedes-1 architectural complex.
The geographic context of Las Mercedes-1, located between streams and rivers on all sides, has raised the question of whether the sphere of influence of a chiefly political center might be bounded by hydrographic systems.
While the causeway ends 1.5 km before reaching Williamsburg, a footpath has been archaeologically identified that may extend the rest of the way connecting these sites.
[20] Both of these excavations revealed rectangular, box-shaped, stone-lined graves, most of which had cobblestone walls with both a flat limestone floor and roof.
[25] In 1871 Las Mercedes was bisected by the construction of the railroad connecting the country's capital to Puerto Limón on the Caribbean coast.
[27] Minor C. Keith, the American commissioned to construct the railroad (and the principle founder of the United Fruit Company), came across a gold artifact at Las Mercedes.
This discovery inspired Keith to not only conduct non-scientific excavations at Las Mercedes, but also to collect artifacts from all over Costa Rica.
[31] During the winter of 1916-1917 Alanson Skinner conducted archaeological excavations at Las Mercedes, Anita Grande, and Costa Rica Farm Site.
During May and June 2005 Ricardo Vásquez, an archaeologist from the Museo Nacional de Costa Rica, and Dr. Claude Chapdelaine with a group of his students from the University of Montréal, Canada conducted an archaeological field-school.
[33][34] In the winter of 2009, between January 11 and February 22, a group of archaeologist from the Museo Nacional de Costa Rica and the State University of New York at Albany (UAlbany), led by Ricardo Vásquez and Robert M. Rosenswig, conducted further investigation.
During this archaeological field school a number of important discoveries were made, which caused Las Mercedes to make the news[35][36]