Joe Ray for The New York Times  Site 1, Plain of Jars, in Laos.  STUFFED with passengers and piled high with luggage, our minivan careened down a twisting mountain road, descending across northern Laos. The spot where I got carsick, I later learned, was precisely where the unfinished French colonial road had reached its westernmost end in 1932.  That year, an archaeologist named Madeleine Colani took refuge at the road works encampment there, where a Monsieur Ruffet presided over the construction of Route 7, which would run from Hanoi, the capital of French Indochina, to the royal city of Luang Prabang on the Mekong River. Though Monsieur received Mademoiselle and her crew amiably, troubles awaited them at his camp that far exceeded my own temporary discomfort.  “The few laborers we had with us ran away one by one without even asking for their wages,” Colani later wrote in her 1935 book, “The Megaliths of Upper Laos.” “Dengue reigned at the site; my sister, my Laotian interpreter and some of the faithful laborers took ill. ... It was May, season of the first strong storms; it was urgent to get back to the Plain of Jars before the route was cut off.”  I too wanted to get to the Plain of Jars, though at the moment mainly so that I could be released from our lurching vehicle. I didn’t have to worry about bad weather leading to an inaccessible route, but I did wonder, as we banged in and out of yet another pothole, if the road had been improved at all in the eight decades since M. Ruffet left.  The Plain of Jars is an area of the Xieng Khouang plateau of Laos scattered with thousands of megalithic stone jars that are about 2,000 years old. They are grouped into clusters that range from just a few to hundreds. The tallest jars reach nearly 10 feet high.  Colani, who was born in France but spent years conducting archaeological surveys in Southeast Asia, was, in more ways than one, the reason I was here. First, she is the source of most of what is known about the jars and their makers. There are local legends about their origin — one says that a tribe of giants used them as wine chalices to celebrate a great victory. But after many months of fieldwork, Colani suggested convincingly that they were used in funerary rites, intended to hold cremated remains. For decades beginning in the 1940s, the region was ravaged by war; archaeologists started to build on her work only in the ’90s. Since then, they have had to tiptoe around the unexploded bomb parts that still litter the landscape from American carpet bombing in the late ’60s, when the United States and Vietnam fought a proxy war there.  Relative to other Iron Age civilizations, the jar makers remain mysterious, and I was attracted to this hole in the historical record. But I had become just as intrigued by Colani herself, the woman who tried to fill in the blanks. Who was this Frenchwoman who had withstood actual hardship — as opposed to the kind a dose of Dramamine can fix — to solve an ancient riddle?  Diminutive and partial to all-black attire, Colani explored the jars under the auspices of the École Française d’Extrême-Orient, a French scholarly institute dedicated to the study of Asian civilizations. Its director, Georges Coedès, called her “the doyenne of Indochinese geological and prehistoric studies” in his obituary of her for the weekly newspaper Indochine. She was born in Strasbourg in 1866 and, at 32, traveled to Indochina, where she taught high school. She earned a doctorate back in France, and in her 60s began the archaeological work for which she would become most famous. She died in 1943 in Hanoi at the age of 76, five months after the death of her sister and assistant, Eléonore. “I know few men in the prime of their lives who would be capable of redoing under the same conditions what these two valiant women accomplished,” Mr. Coedès wrote.
An area of northern Laos is studded with thousands of stone jars. Who built them, and why? The author follows the story of a woman who tried to find out.