By John Whatley

Thousands of years before the pharaohs raised pyramids in Egypt, and before the Greeks and Romans conquered the world, a group of farmers on the rugged northwest coast of Ireland cleared their lands, built their houses, walled their fields, planted their crops, fed their animals, and lived their lives. Expanding throughout the adjacent valley and over the ridge into the valley immediately south, this community would cover several square miles and be home to hundreds of farmers. 

But that was 5,000 years ago. Today, the farmers are all gone, but, unlike Egypt, Greece, and Rome, where civilization after civilization has built over ancient sites, their settlement still exists. It is kept in pristine condition because of an unintended ecological disaster: an enormous peat bog, 12 feet deep in places, called the Céide (pronounced KAY-djee) Fields.

On a map of Ireland, Céide is located on the front of the dog’s foot in Co. Mayo (Maigh Eo). It sits about halfway between Belderg to its west and Ballycastle to the east atop a 350-foot-high striated cliff of sedimentary rock. Beneath this base lies an even older formation of igneous rock. Warped and refolded like bread dough by enormous heat and pressure, then eroded by waves, this hard rock layer finally sank beneath the sea. There over millions of years a thick seabed of dark shale, khaki sandstone, and light limestone deposited on it before the cliffs rose from the sea.

Céide’s farmers cleared the forests from this land for planting, using the timber to build their houses. But this loss of the trees eventually changed the environment. The trees, whose absorbing roots had gradually released rainfall to canopy evaporation, were no longer there. Céide’s annual 240 days of rain left the cleared landscape moister and moister. Nutrients leached away. Plants now held onto their moisture. Cycles of life, death, and decay to the soil were disrupted. 

Mosses and other plants which thrived on poor soils expanded their range, forming bogland. Over several centuries the farmers were forced out by poor soil, overabundant moisture, and an ever-expanding peat bog – what’s been called a "slow motion Pompeii." This peat bog, however, preserved Céide as an unspoiled archeological site.

In other ancient sites around the world, people have continued to live in the area, changing the history and the landscape. Farmers have expanded or contracted their holdings, changing from crops to cattle and back again. Cities have risen and fallen over old settlements. Some have been conquered by different cultures. Studies at sites in Rome or Jerusalem are difficult because of the concurrent changes. But at Céide the bog covered the entire site, preserving Céide intact for eons until it was accidentally rediscovered in the 1930s by peat harvesters.

Peat bogs are a fuel source for the people of Ireland. A peat bog is mostly water because of the undecayed plant material in it. When peat is cut into "sods" and set out to dry, it contracts and becomes firm. Resembling a brick of coal, it makes an excellent household fuel. A bank of peat 300 feet long cut seven sods wide and four sods deep provides enough fuel for a family for a year.

Back in the 1930s, Patrick Caulfield noticed stones at the bottom of the bog when he was harvesting peat. He noticed two other things: the stones were stacked and not naturally-occurring, and they were on the bottom of the bog. His son, Dr. Seamus Caulfield, became an archaeologist and began to investigate the area. The stones were found to be part of a wall system. The original accidental uncovering was "free archaeology," but tracking these walls using traditional archaeology – digging down to the walls through the peat – would be labor-intensive and cost-prohibitive. 

Fortunately, bog workers for centuries had used long metal probes to find trees buried in bogs. By pushing these probes into Céide’s bog, the firm original soil layer was easy to find. Then a bamboo pole the length of the probe was inserted to rest atop the original soil. When probes eventually hit the buried walls, the bamboo poles stood higher. By viewing the level of the poles, the walls could be tracked, and the outline of rectangular walled fields began to appear. Using this primitive manner and volunteer labor, the walled fields over some four square miles have so far been mapped.

Céide was a community of hard-working farmers. First, they cleared the land. Next, they built their dwellings. Then they bordered their lands with rocks. It is estimated that there are some quarter million tons of rocks bordering the fields lying under Céide. This clearing of trees and walling of the land required cooperation from a sizable community. Archaeologists theorize the large rectangular fields were probably for cattle, while the smaller fields were for growing wheat and barley, since the cutting part of a primitive plow has been found at Céide. Material found at a hearth at Céide has been radiocarbon dated to 3000 BC. So far no defensive walls have been discovered, meaning this large community lived in peace. 

In 1989, Dr. Caulfield and Prof. Martin Downes undertook improving the site. In 1993, the Céide Fields Interpretive Center, an award-winning pyramid-shaped building, was opened on the site by the Office of Public Works. It is now run by Dúchas, The Heritage Service. A 5,000-year-old tree trunk, mounted under the open pyramid top, is the centerpiece of the Center. Around it are dioramas of how anthropologists believe the Céide people lived. Also, cuts have been made through the bog down to the level of the walls. Guided tours of the bogland tracing the walls are also available.

While strolling across the bogland, it is difficult to believe that underneath lies the pristine remains of an ancient civilization – a civilization preserved in time because the inhabitants unintentionally set in motion an ecological disaster.