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.
Location
Las Mercedes is located 90 m above sea level in Mercedes District, Guácimo, Limón Province, Costa Rica between the rivers Dos Novillos and Parismina, which are tributaries to the Reventazón River. Dos Novillos River is 700 m to the southeast and Parismina is 2.5 km to the northeast of the site.
Description
With a size of 25 hectares, Las Mercedes is divided into 3 large complexes: Las Mercedes-1, Las Mercedes-2, and Las Mercedes-3. However, only Las Mercedes-1 has been extensively studied. Recent excavations at Las Mercedes-1 (L-289 LM-1) have revealed that it has an area of 5 hectares and consists of 7 platforms, 2 plazas, 6 retaining walls or terraces, 7 walls, 4 funerary areas, 1 ramp, and is where the 2 roads converge.
Chronology
Investigations in this part of the site have determined that the site was occupied from circa 1500 BC to circa AD 1500 and that monumental architecture began being constructed around AD 1000. 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. This indicated that trade may have occurred between the Las Mercedes inhabitants and the Spanish.
Platforms
In all, Las Mercedes has at least 15 platforms. Three of these platforms are located around a principal/central platform (known as the Hartman Platform), and are united by intra-site causeways. The Hartman Platform (R1) is 6 metres tall and has a diameter of 30 metres. It was first excavated by C. V. Hartman who removed two 1.85 male stone male "warrior" figurines among other artifacts. Today these sculptures are housed at the Museum of Ethnography, Sweden.
Three of the 15 platforms have been studied more extensively. Platform R12 is circular, 1 metre tall, and has a 28-metre diameter. Moreover, this platform is accompanied by 7 metre wide, 30 metre long ramp or causeway (R11), which connects to a stone terrace (R10). The second most studied platform (R9) is actually two conjoined platforms with a figure eight shape. The circular part has a 25-metre diameter and the oblong part measures 22x20 metres. The third of these platforms (R14) has an irregular shape "like a peanut" according to archaeologist Ricardo Vásquez.
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.
Causeways
Las Mercedes is the home of two well-documented stone-paved roads, named The Iroquois Causeway and The Pocora Causeway for the present-day towns they lead towards from the main architectural complex of the site. With widths ranging between 5 and 8 meters, they follow a northwest to southeast path, running perpendicular to the river drainage system. The research to date has registered much data about The Pocora Causeway, whereas our knowledge of The Iroquois Causeway will never be complete due to its alteration and partial destruction over the years. The straight stone-paved Iroquois Causeway has been followed for about 660 m at the edge of the EARTH University reserve that contains the site. However, researchers predict that it extended as far as the Iroquois settlement. Although The Iroquois Causeway has not been followed in its totality, it may be presumed that it is of a comparable length to The Pocora Causeway, based on their similarity in design.
The Pocora Causeway begins in the main complex and extends for an indefinite distance, going beyond the zone southeast of the complex, where it was not possible to clear vegetation during the 2005 field season. The Pocora Causeway continues for more than 300 m, running parallel to a secondary road, which connects to the Dos Novillos River. This causeway was raised above the surface as a protective measure against flooding. When The Pocora Causeway reaches its southeast extent, it comes to an end intersecting with a small stream known as Santa Emilia. Just before it reaches the stream The Pocora Causeway is flanked by an architectural complex consisting of two low walls with circular halves on the southeast side (R31 & R32), resembling those of the main complex. A set of stairs (R33) between the circular structures, descends to the stream.