Each year hundreds of people go missing in United State Parks and National Forests. Most investigations are eventually solved through reasonable causes: foul play, drowning, suicide or an animal attack. Others aren’t quite so easy to dismiss. Many of them are not merely perplexing but outright disturbing. The Missing 411 books take a deeper look into these specific situations which seem to defy all logic.

Author of the series, David Paulides, is a private investigator who served as a Los Angeles police officer for over twenty years. One day he stumbled upon some shocking information from a park ranger. They informed  Paulides about a series of bizarre missing persons cases happening within the National Parks. According to this source, these individuals go missing under very unusual circumstances. Law enforcement officials and park service management were doing everything in their power to keep these events concealed from the general public.

When Paulides attempted to obtain a list of missing people in Yosemite National Park he hit the first of many roadblocks. He was told that there is no such document because the Department of Interior does not keep any record of missing people within their park systems. To obtain this information would cost him $34,000. A list missing persons for the entire United States park systems was a staggering $1.4 million. Paulides did not oblige and instead filed hundreds of Freedom Information Acts. Some were accepted while others were denied for unknown reasons.

As the investigation progressed, the more mysterious it became. One of the first things that was discovered were the presence of “clusters” throughout the country. These locations are hotspots where individuals disappear at surprisingly high numbers. Concentrated areas are present in many states including California, Colorado, Washington, Georgia, Michigan and Arkansas. Fifty-two clearly defined geographic regions have been identified.

After meticulously researching thousands of cases, odd similarities and patterns emerged. Certain baffling parallels were seen repeatedly despite the incidents transpiring thousands of miles from each other. Some of the common links are difficult to rationalize and not easily dismissed. These perplexing characteristics leave far more questions than answers.

• Search dogs behave strangely. Oftentimes these canines cannot pick up a scent, or simply don’t want to. In other instances they begin tracking only to lay down and stop searching as if the person had vanished into thin air. Cadaver dogs are unable to locate a corpse.
• The body is found in an area that has searched before. In many instances the missing appears in a location that has been thoroughly searched dozens, if not hundreds, of times. It is not uncommon for the deceased to surface on a main trail that is utilized by hikers on a daily basis.
• Travel uphill instead of downhill. The missing is often found at high levels of elevation, such as mountain peaks. Frequently the victim will travel an astounding amount of miles through treacherous terrain in a time period which seems humanly impossible.
• Weather-related phenomenon. Shortly after the individual goes missing, the forecast takes a drastic turn. Torrential rain, lightning, fog, sand storms or blizzards occur which delay search parties.
• Missing clothing. Shoes, pants, shirts and jackets are often removed, even by children who are too young do so themselves. Paradoxical undressing cannot explain why a person would do this in a temperate environment. Clothing that is found is sometimes neatly folded.
• High amounts of plane crashes. Search planes and helicopters seem to crash at abnormally high rates during these specific cases.
• Extreme ends of the intellectual scale. On one side there are well-educated people such as doctors, psychiatrists and physicists. Others have disabilities such as autism or Down Syndrome.
• German ancestry. Those with German heritage appear to go missing at much higher rates.
• Boulder fields and granite. An excessive number of men and women vanish in boulder fields or areas with huge quantities of granite. Yosemite National Park is the largest of all clusters and also happens to be the biggest source of granite on Earth.
• The victim is retrieved near a body of water. Another common factor is the presence of water. Bodies are often discovered near oceans, lakes, rivers, streams or swamps.
• Berry picking. Strangely, this is a reoccurring theme shared amongst several cases. Those who are picking berries seem to go missing at higher rates.
• Not feeling well or being tired. Prior to the disappearance, friends and family state the victim had informed them that they were feeling ill or weary.
• Being last in line. One of the most recurrent of all traits are those in a group who happen to be the last in line. Others who were with the missing report seeing them mere seconds before and suddenly they had vanished without a trace. No one ever reports hearing any sounds such as a gasp, scream or an animal.

The NPS employs over 20,000 Americans and brings in an annual revenue $92 billion. If patrons knew what was really happening within the park systems it could have devastating financial consequences. Paulides has never stated who (or what) he believes is responsible for these incidents and merely presents the facts. Readers are left to derive their own conclusions based on the information presented. Theories as to what is taking these park-goers include Bigfoot attacks, alien abduction, Thunderbirds, secret underground government bases or cannibalistic wild men. Whatever the source may be, it’s probably best to avoid being last in line the next time you visit a National Park.