Formation · Central
Areniscas columnares del Cerro Kõi
Sandstone that split into five- and six-sided columns when volcanic dikes heated it: a geological rarity 30 km from Asunción.
Nature
Nature of Paraguay
Paraguay has no coastline, but it has the nature of an entire continent. Within its borders you'll find the Chaco, the southern tip of the Pantanal, the Cerrado, the last remnants of the Upper Paraná Atlantic Forest and the great marshes of the south. This is home to the jaguar, the giant armadillo, the maned wolf and the Chacoan peccary, or taguá, a species known only from fossils until 1975, when scientists confirmed it was still alive in the Chaco. More than 700 bird species have been recorded here. Many of these landscapes are under threat, and traveling with local guides is one way to help protect them. It pays to follow the seasons: the pink lapacho (tajy) in bloom at the end of winter, the bellbird calling in spring, and flamingos on the Chaco's salt lagoons.
La historia de la tierra paraguaya: cerros, rocas, cuevas, fósiles y agua subterránea.
Hill · Central
Cerro Ñemby (tapón volcánico de nefelinita)
A truncated cone of volcanic rock in the middle of Ñemby: the remains of a magma conduit that erosion left exposed.
Hill · Paraguarí
Cerro Acahay (complejo alcalino anular)
A ring-shaped massif born from alkaline magma that rose and cooled underground about 126 million years ago.
Hill · Paraguarí
Cerro Yaguarón (cerro relicto de arenisca)
A flat-topped hill of silicified sandstone, with ripple marks and desiccation cracks that tell what the landscape was like millions of years ago.
Hill · Paraguarí
Cerro Perõ (abanicos aluviales antiguos)
A lookout inside the city of Paraguarí made of chaotic rock: blocks dragged down by mud and water flows millions of years ago.
Hill · Paraguarí
Cerro Hũ (arenisca ordovícica)
The typical section of the Cerro Hũ Formation: sands from an ancient river, coarse at the base and finer at the top.
Hill · Paraguarí
Cerro Cristo Redentor (rocas del Neoproterozoico)
Some of the oldest rock in the area: folded Proterozoic metasediments, more than 500 million years old.
Rock · Cordillera
Monolito San Rafael (arenisca con tafoni)
A block of white, sugar-textured sandstone pitted by erosion, on the outskirts of Piribebuy.
Rock · Cordillera
Granitos cámbricos de San Bernardino
Pink granite boulders on the shore of Lake Ypacaraí: rock more than 500 million years old a few steps from the beach.
Formation · Central
Rift de Asunción y lago Ypacaraí
A tectonic trough with up to 2,500 m of sediments that crosses eastern Paraguay and helps explain Lake Ypacaraí and many of its hills.
Fossil · Central
Lutitas fosilíferas de Itauguá (mar del Silúrico)
Shales with trilobites, graptolites and brachiopods from a Silurian sea that covered the region about 440 million years ago.
Formation · Central
Barrancas erosionadas de Ypané (cárcavas del Cuaternario)
Gullies carved by water in recent clayey sands, near where Pleistocene glyptodont fossils have been found.
Hill · Central
Itá Ybaté (Lomas Valentinas): areniscas y batalla
Hills of Ordovician sandstone where a battle of the Paraguayan War was fought: geography that shaped history.
Plateau · Guairá
Cordillera del Ybytyruzú
The country’s highest range, made of Cretaceous lava flows and cut by alkaline dikes at the eastern end of the Asunción Rift.
Hill · Guairá
Cerro Tres Kandú (el punto más alto de Paraguay)
At 842 m, the highest summit in the country: one of the crests of the Ybytyruzú range, on the border between Guairá and Caazapá.
Formation · Alto Paraná
Basaltos del Paraná (Formación Alto Paraná)
A strip of basalt flows along the Paraná River, the remains of one of Earth’s largest eruptions, which came before the opening of the South Atlantic.
Waterfall · Canindeyú
Saltos del Guairá (Sete Quedas), cataratas sumergidas
They were the largest waterfalls by flow on the Paraná River: 18 cataracts in seven groups that the Itaipú reservoir covered in 1982.
Aquifer · Itapúa
Acuífero Guaraní (Formación Misiones)
One of the planet’s largest reservoirs of underground fresh water: in Paraguay, sandstones of the Misiones Formation capped by basalt.
Aquifer · Central
Acuífero Patiño
The groundwater that supplies much of Greater Asunción, stored in the conglomerates and sands of the Patiño Formation.
Cave · Concepción
Calizas del Grupo Itapucumí y cavernas de Vallemí
The country’s largest karst system: 66 km² of Ediacaran limestone with more than 50 known caves, in northern Concepción.
Fossil · Concepción
Fósiles ediacáricos de Vallemí (Cloudina y Corumbella)
In the Vallemí limestones lie some of the first animals with skeletons: Cloudina tubes and Corumbella remains.
Cave · Amambay
Dolina Kururu Kua (cenote en arenisca)
A crystal-clear water-filled shaft about 130 m deep down to its collapse cone, sunk into soft sandstone: the first sinkhole in sandstone described in Paraguay.
Formation · Amambay
Formación Aquidabán (huellas de una glaciación)
Layers of clays and boulders in the Alto Apa region that many geologists interpret as glacier deposits more than 300 million years old.
Formation · Presidente Hayes
Cuenca del Chaco (llanura de sedimentos)
A plain of fine sands and clays carried down from the Andes: the Chaco makes up almost 60% of the country and has almost no visible bedrock.
Formation · Presidente Hayes
Abanico del Pilcomayo y Estero Patiño
The Pilcomayo shifts its course and drops so much sediment that it built South America’s largest alluvial fan; Estero Patiño dried up because of it.
Salt flat · Boquerón
Lagunas saladas del Chaco Central
Shallow lagoons whose water alternates between fresh and brackish, with salinised soils at the edges: an evaporation landscape in the heart of the Chaco.
Formation · Alto Paraná
Tierra colorada (suelos rojos del este y sur)
The red of the roads in Alto Paraná and Itapúa comes from iron in basaltic rocks and sandstones broken down by centuries of heat and rain.
Formation · Boquerón
Sismicidad: por qué Paraguay tiembla poco
Paraguay sits in the middle of the South American plate: earthquakes are rare and moderate, the largest on record being M5.6 in Boquerón in 1989.
Mineral · Guairá
Oro de Paso Yobái
A district in Guairá with gold mining since the mid-1990s, which today mixes prosperity with environmental debates.
Formation · Concepción
Alto Apa (basamento más antiguo del país)
In the north, along the Apa River, the country’s oldest rocks crop out: a craton more than a billion years old that forms the base of the Vallemí limestones.
Rock · Paraguarí
Alto Caapucú (granitos y gneises del sur)
The northwesternmost outcrop of the Río de la Plata Craton: granites, gneisses and migmatites that erosion rounded into blocks.
Tips
- Bring binoculars and log what you see on eBird or Merlin: data from visitors helps local science.
- For the deep Chaco, the Pantanal and remote parks, hire local guides or baqueanos (backcountry guides), travel by 4x4 with spare water and fuel, and notify the park rangers in advance. Many areas have no cell signal.
- The best time for the Chaco is May to September. In summer the heat tops 40 °C and rain makes dirt roads impassable.
- Use insect repellent, long sleeves and closed shoes: there are mosquitoes, ticks and venomous snakes such as the yarará. Watch where you step and don't put your hands into holes.
- Before traveling, check current vaccination recommendations (for example, yellow fever outside Asunción) and protect yourself against dengue.
- Don't buy wild animals, skins, feathers or parrots: wildlife trafficking is one of the biggest threats and is prohibited under the wildlife law (Law 96/92).
- On Chaco roads, drive slowly at dawn and dusk: anteaters, foxes, armadillos and even pumas cross the road and are killed by vehicles.
- Sport and commercial fishing have an annual spawning closed season: it usually starts in early November and runs until late December (until late January in waters shared with Brazil). Check the dates published by MADES before you go and get a fishing license.
- Between August and October the risk of wildfires is high, especially in the Chaco and the Pantanal: don't light fires outside designated areas.
- If you pass through Indigenous communities, ask permission before entering or taking photos, and whenever possible buy crafts directly from the people who make them.
- To see the lapachos in bloom, plan your trip between July and September. In Asunción, the streets and squares turn pink and then yellow.