Ulster County and some of its communities – notably Woodstock and New Paltz – have developed a reputation over the past decades as places hospitable to outside-the-box thinkers. So when Erich von Däniken’s Chariots of the Gods? became a blockbuster best-seller in 1968, there were definitely plenty of people around these parts who were willing to entertain his controversial hypothesis: that extraterrestrial visitors had played pivotal roles in nudging along ancient human cultures toward technological breakthroughs that, von Däniken argued, would otherwise have been beyond their capacities.

It was in this context that most average folks first heard of Peru’s amazing Nazca Lines, and I suspect that many of us haven’t thought much more about them since von Däniken’s reputation as a researcher began to fall apart. While admitting that “paleo-contact” between humans and extraterrestrials is at least theoretically possible, reputable scientists promptly dismissed von Däniken’s work as “pseudoarchaeology.” The Swiss author did time for tax evasion, fraud and embezzlement, and later admitted that much of the evidence that he had put forward for his “ancient astronauts” hypothesis was fraudulent. Meanwhile, the science-fiction-writing community – at first receptive as usual to challenging new ideas – was quick to note the close parallels between von Däniken’s speculations and the plotlines of the Cthulhu Mythos cycle of horror fantasy tales by H. P. Lovecraft. All this, of course, has not deterred continued popular speculation about UFO contacts; and at least one erstwhile Ulster County resident, Whitley Strieber, went on to turn accounts of alien abduction from his summer cottage in Accord into a lucrative cottage industry with his book Communion and its many sequels.

But what about those crazy designs – lines, grid patterns, geometric forms and huge plant and animal figures carved into the soil, including a monkey, a dog, a spider, a lizard, a llama, a couple of fish and quite a few birds – that span an area of nearly 190 square miles in the high desert plateau of southern Peru? We have a pretty good idea nowadays of how they were laid out and executed: Remnants of wooden stakes have been found at the ends of some of the markings, from which cords were likely suspended in the same way that a carpenter snaps a chalk line to mark the base of a wall in a building under construction. Research teams using archaic tools were easily able to replicate the Nazca lines and designs by excavating trenches about six inches deep to expose the lighter-colored subsoil – the same primitive technology by which Iron Age Britons carved their great white horses and the Cerne Abbas Giant into the chalky hillsides of southern England.

What we still don’t know for sure about the Nazca lines is why they were made. They may not have been signals to alien gods or runways for incoming flying saucers, as von Däniken alleged; but they still exert a compelling hold on the imagination and have continued to inspire myriad attempts at explanation. Some of the latter have been nearly as fanciful as those put forth in Chariots of the Gods? Since the patterns can only be seen in full perspective from the sky, one fellow attempted to prove that the Nazca people must have been flying hot-air balloons 1,500 years ago. Slightly less of a stretch is an art historian’s notion that the longer lines were used to stake out gigantic looms for the weaving of extremely long fabric panels for use as winding-sheets, since the Nazcas found the high plateau’s arid climate convenient for mummification of their dead. Other attempts to construe the alignment of the markings as some sort of observatory marking the rising and setting points of planets and other astronomical phenomena have not stood up well to scientific testing.

Of all the hypotheses offered so far, the most credible-sounding have had to do with the high-desert climate of the site and the unreliability of local water sources for irrigating fields to grow crops. (Ironically, there is growing concern in the scientific community that climate change may increase annual rainfall on the plateau and eventually obliterate the lines, until now so well-preserved.) Various archaeologists have speculated that the large animal figures signify supplication to the Nazca pantheon for help in obtaining water; that the straight lines point towards springs in the nearby mountains; or that the winding lines are sacred paths meant to induce a hypnotic meditative state, just as spiral labyrinths have been used for many centuries in Western spiritual practice.

More recently, Dave Johnson – a hydrologist who has served as one of the experts on the National Geographic Society’s Committee on Research and Exploration – made what may prove to be a significant breakthrough: While working to help the city of Nazca identify new water sources, he discovered that the Nazca lines align with the geological faults and aquifers that he was mapping in the region. Johnson will be giving a lecture on his findings this Saturday, February 5 from 3 to 4:30 p.m. at the Mohonk Preserve, titled “The Nasca Lines: Theory & Discovery” (utilizing an acceptable, though not prevalent, alternate spelling).

This program takes the audience on an intriguing journey that examines the ancient Nascan culture and the clues that enabled Johnson to come up with a plausible solution to one of the world’s most elusive ancient mysteries. It concludes with a display of 1,500-to-2,000-year-old textiles, tools and pottery from southern Peru.

Ages 16 and up are welcome; children must be accompanied by an adult. Reservations are required. The fee per person is $5 for Mohonk Preserve members, $10 for non-members. Call (845) 255-0919 for reservations and the meeting location; this is an indoor program. Payment is required at the time of registration. The snow date is Sunday, February 6.