- Where
- Diquís Delta, Palmar Sur
Osa, Puntarenas, Costa Rica - Coordinates
- 8.93° N
83.48° W - Spheres
- More than 300 known
a few cm to over 2 m across - World Heritage
- 2014: Finca 6, Batambal,
El Silencio, Grijalba-2 - National symbol
- Since 2014
- Getting there
- Road from San José
to Palmar, then the Sierpe road - Best visited
- December to April (the dry season)
- Advisory
- Costa Rica Level 2 (crime)
Hot and green and dripping, with palms planted in rows all the way to the hills, and in a clearing at the edge of it all, stone balls: big ones and small ones, smooth as river pebbles, waiting on the grass in a line. I walked round the largest twice, slowly, and did not touch it. It did not seem the kind of thing you lean on.
The short answer
The stone spheres of Costa Rica, also called the Diquís spheres or las bolas de piedra, are more than 300 carved stone balls found on the Diquís Delta, the alluvial plain of the Térraba and Sierpe rivers in the south of Puntarenas Province, and on Isla del Caño offshore, Wikipedia records. They range from a few centimetres to over 2 metres across and weigh up to about 15 tonnes. Most are gabbro, a hard, coarse-grained igneous rock; a dozen or so are shell-rich limestone and another dozen sandstone. In June 2014 UNESCO inscribed four settlements with spheres, Finca 6, Batambal, El Silencio and Grijalba-2, as the Precolumbian Chiefdom Settlements with Stone Spheres of the Diquís; the next month Costa Rica declared the spheres a national symbol. Finca 6, on the road from Palmar Sur to Sierpe, is the one site set up for visitors, with a small museum run by the Museo Nacional de Costa Rica and spheres still standing where they were found.
Why it's worth knowing
Found by bulldozer, opened by dynamite. The spheres came to light in the 1930s, when the Compañía Bananera de Costa Rica, a branch of the United Fruit Company, cleared the forest of the delta for plantations. Workers shoved them aside with heavy machinery and, inspired by stories of gold hidden inside, drilled holes in some and blew them apart with dynamite before the authorities stepped in, Wikipedia records. Some dynamited spheres were pieced back together and are shown at the Museo Nacional in San José. Many more were hauled away to decorate gardens and public buildings around the country; Finca 6 has become a home for spheres returned to the museum.
Made by hand, set in lines. The spheres appear to have been shaped by hammering natural boulders with other stones and then polishing them with sand, and the finish varies a good deal from one to the next. The gabbro came from the hills several kilometres away, where some unfinished spheres still lie. Many were set in lines, which archaeologists think marked the approach to the houses of chiefs, though what the spheres meant is not settled, Wikipedia says. Its article on the Diquís culture lists the readings that have been proposed: symbols of rank and power, territorial markers, or aids to tracking the sun and the seasons.
How old, and how round. Wikipedia’s two articles do not agree on the age. Its article on the spheres says they were first made around 600 CE, most after 1000 and before the Spanish conquest, and adds that the only way to date them is by the layers they lie in, which fails when a sphere has been moved; its article on the Diquís culture gives 300 BCE to 300 CE. The roundness has its own legend. The archaeologist Samuel Lothrop published tables of diameters to three decimal places in 1963, which fed claims of near-perfect spheres; Wikipedia records that those figures were averages of measurements taken with tapes nowhere near that precise, and that some spheres vary by more than 5 cm across.
The field notes
The first to look closely
The first study of the spheres was by Doris Stone, the daughter of a United Fruit executive, published in American Antiquity in 1943. It drew Samuel Lothrop of Harvard’s Peabody Museum, who in 1948 went to the delta at her suggestion and spent years recording spheres where they lay, their sizes and their alignments, Wikipedia records. His Archaeology of the Diquís Delta, Costa Rica appeared in 1963. Since 2002 the Museo Nacional’s archaeologists Francisco Corrales and Adrián Badilla have studied the four sites that now make up the World Heritage property.
Finca 6
Finca 6, Farm 6, was a United Fruit plantation block. Its site of about 10 hectares on the Térraba floodplain held a settlement and a cemetery, and has two mounds built with retaining walls of rounded river cobbles, with spheres found in place beside them; excavations by the Museo Nacional began in 2005, and in 2007 a sphere was found in place against the first mound, Wikipedia records. The finds date from the Aguas Buenas period (300–800 CE) and the Chiriquí period (800–1550 CE). In July and August 2025, conservators from the Museo Nacional and Mexico’s National School of Conservation, Restoration and Museography restored three limestone spheres at Finca 6, originally found at Finca 4, which had suffered from water erosion, cracking and micro-organisms (Archaeology magazine and HeritageDaily, September 2025, as indexed).
Myths, and a thunder god
The spheres have gathered stories: that they came from Atlantis, that they formed naturally, or that their makers had a potion to soften rock. Wikipedia answers the last by noting that most spheres are gabbro, which resists acids. The Bribri tell their own story, as Wikipedia records it: the spheres are the cannon balls of Tara, the god of thunder, who fired them from a giant blowpipe to drive the gods of the winds and hurricanes from the land. The word diquís means “great waters” or “great river” in the Boruca language, by Wikipedia’s account.
Late sun on a sphere among palm roots, January 2026.
Photograph: xiquinhosilva (Xiquinha Silva) · CC BY 4.0
The surface of a sphere, worked smooth.
Photograph: François Bianco · Diquis Stone spheres (15272809254) · CC BY-SA 2.0
- Arrive at opening time, while the grass is still wet from the night, and give the little museum its due before walking out to the field.
- Walk where the paths go. Part of this ground was once somebody’s cemetery.
- Count the spheres. (Attempted. Lost count at the mound, started again, arrived at a different total. Both are kept, next to each other, in pencil.)
- Ask a guide which of them were found just where they stand, and write the answer down beside each one.
- Pack water, a sun hat and some patience for the rain, which keeps its own hours.
A sphere where it was left. At Finca 6, on the floodplain of the Térraba, some of the spheres still lie in the places where the Museo Nacional’s archaeologists found them, beside the cobble-walled mounds of a settlement that also held a cemetery. Each was hammered out of a boulder with other stones and polished with sand, by Wikipedia’s account, and the gabbro for them came from hills several kilometres away. Spheres found where they were set are the ones that can still say something about how they were arranged; most of the others were moved long ago.
Tally, in the marginI had expected something written on it, a carving, a sign of who made it. Only after a long, slow circuit did I see that the roundness was the whole message, and that it had been said very carefully.
Getting there
How to get there. Finca 6 is on the paved road from Palmar Sur to Sierpe, in the south Pacific of Costa Rica. The Museo Nacional’s brochure, as indexed, puts it 9.5 km from the Térraba bridge; travel guides give 7 to 8 km from Palmar. Buses run from the TRACOPA terminal in San José to Palmar Norte, about five hours (route planners, as indexed); from Palmar, a taxi or car covers the last stretch. Sierpe, a few kilometres on, is the boat town for the Osa Peninsula, so the two can share a trip.
When to go. The site museum is open Tuesday to Sunday, 8 a.m. to 4 p.m. (the museum’s brochure, as indexed). December to April is the dry season in Costa Rica and May to November the rainy season, Wikipedia records, and the Térraba has flooded the plain in storms, as it did during Tropical Storm Nate in October 2017.
What to arrange ahead. Nothing beyond transport. Entry is a modest museum ticket bought at the gate (the brochure, as indexed, gave $6 for foreign adults; a travel blog in 2026 gives $7). Allow about two hours for the exhibition and the walk to the mounds and sphere alignments.
Safety. The State Department has Costa Rica at Level 2, exercise increased caution, due to crime (advisory dated 2 April 2026 in its feed, read 7 October 2026). It says petty crime is common throughout the country and that violent crime, including armed robbery, homicide and sexual assault, also affects tourists; it names no particular area. Ordinary care with valuables and vehicles applies here as anywhere in the country. Check the weather and the river in the rainy months.
Mark this place
Common questions
Where are the Diquís stone spheres?
The Diquís stone spheres are found on the Diquís Delta, the plain of the Térraba and Sierpe rivers in the south of Puntarenas Province, Costa Rica, and on Isla del Caño. The site set up for visitors is Finca 6, on the road from Palmar Sur to Sierpe.
How many stone spheres are there in Costa Rica?
More than 300 stone spheres are known from Costa Rica’s Diquís Delta and Isla del Caño, Wikipedia records. They range from a few centimetres to over 2 metres across and weigh up to about 15 tonnes; most are carved from gabbro.
How old are the Costa Rican stone spheres?
The age of Costa Rica’s stone spheres is uncertain. Wikipedia’s article on the spheres dates the first to around 600 CE and most to after 1000; its article on the Diquís culture gives 300 BCE to 300 CE. They can only be dated by the soil layers around them, and most have been moved.
What were the stone spheres of Costa Rica for?
No one knows for certain. Many of the Diquís spheres were set in lines near the houses of chiefs, and archaeologists have read them as symbols of rank and power, as territorial markers, or as aids to tracking the sun and the seasons. None of these has been settled.
Are the Costa Rican stone spheres perfectly round?
No. Claims of near-perfect roundness grew from Samuel Lothrop’s 1963 tables, which gave diameters to three decimal places; Wikipedia records that these were averages of tape measurements far less precise than that, and that some spheres vary by more than 5 cm in diameter.
Can you visit the Diquís stone spheres?
Yes. Finca 6, near Palmar Sur, is run by the Museo Nacional de Costa Rica as a site museum with spheres still in place, open Tuesday to Sunday from 8 a.m. to 4 p.m. Other Diquís spheres stand in San José, at the Museo Nacional and in public buildings.
When did the Diquís stone spheres become a World Heritage site?
UNESCO inscribed the Precolumbian Chiefdom Settlements with Stone Spheres of the Diquís in June 2014: Finca 6, Batambal, El Silencio and Grijalba-2, in southern Costa Rica. Costa Rica declared the stone spheres a national symbol the following month.
Why were some of Costa Rica's stone spheres blown up?
In the 1930s and after, workers clearing the Diquís Delta for banana plantations heard stories of gold hidden inside the stone spheres, drilled holes in some and blew them open with dynamite, until the authorities intervened. Some were reassembled and are shown at the Museo Nacional in San José.