The Gabby Petito case is the latest in a long line of mysterious deaths, disappearances and murders that have occurred in national parks around the United States.
The body of Petito, 22, was discovered at the edge of Grand Teton National Park in Wyoming over the weekend. Investigators have not said how she died but a medical examiner on Tuesday ruled the manner of death a homicide. Authorities have identified her fiancé Brian Laundrie, who was reported missing by his parents in Florida, as a person of interest in the case.
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The young couple had set out in July in a converted van headed west to Oregon. They planned to visit several national parks along the way -- just two of the tens of millions of travelers who visit the country's 63 national parks each year.
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While most park visits are danger-free, according to a dashboard from the National Park Service that analyzed deaths in parks from 2014 to 2016, there were about 6 deaths per week in the national parks, or an average of 330 deaths per year. The park mortality rate is about one death for every million visitors.
The dashboard said 53 percent of deaths in the parks were due to unintentional causes, including falls, car crashes and drownings. Of the intentional deaths, about 95 percent were suicides, according to the National Park Service.
The park service doesn't appear to have more recent death figures and the dashboard doesn't say how many of the unintentional deaths are homicides.
But the NPS does keep a web page dedicated to cold cases in the parks, including unsolved murders and other unexplained disappearances and deaths.
Double Murder at Shenandoah
Perhaps the most infamous national parks homicide case involves the killings of Julianne Williams and Laura Winans, who were found murdered at a campsite at Shenandoah National Park in Virginia on June 1, 1996.
Williams, who was 24 at the time, and Winans, who was 26, had been last seen hiking with a Golden Retriever on May 24.
The women's bodies were discovered by searchers after their dog was spotted wandering alone a hiking trail. Media reports at the time said they had been tied up and had their throats slashed.
The FBI and National Park service are still investigating the murders.
Boy Vanishes at Crater Lake
One of the more unusual unsolved disappearances at a national park is the case of 8-year-old Samuel Boehlke, who vanished on Oct. 14, 2006, while on a trip to Crater Lake National Park in Oregon with his father.
A massive search was initiated but no trace of the boy was ever found.
The National Center for Missing and Exploited Children later released an age progressed image of what Boehlke might look like at age 19.
Homicide at Hawai'i Volcanoes
Hawai'i Volcanoes National Park may be one of the premier spots in the country to view active volcanoes, but on April 13, 2005, it was the scene of a murder.
On that date, the body of Arman Johnson was found by a park visitor near Kahuku Ranch, close to the park's southern boundary.
Johnson, who was 44 years old at the time he was killed, had moved to the Big Island from Seattle, Wash. in 1984, and hosted a local radio show.
Though the suspect and motive remain unknown, authorities said evidence indicates Johnson suffered a single gunshot wound to his upper back/neck.
Investigators believe the murder, which remains unsolved, took place where the body was found.
Murdered Jane Doe Found at Yosemite
Yosemite National Park in California also became the scene of a murder investigation in the spring of 1983 after the partial remains of a homicide victim were found in the park's Summit Meadow along Glacier Point Road.
Forensic anthropologists believe the victim was at least in her late teens but could have been as old as 30.
Authorities said the suspect in the case, Henry Lee Lucas, was interviewed in the 1980s and died in prison in 2001. He had information about the murder that had not been made public and could only be known by the person who committed the crime.
Lucas stated the victim was a female hitchhiker that he picked up on Highway 41 between Fresno, Calif. and Yosemite National Park in the early 1980s.
The woman's remains have never been identified and she is still only known as Jane Doe.
Lucas was convicted of murdering 11 people, though some of the killings were later disputed.
Chiricahua Ranger Disappears
The last time anyone saw Paul Braxton Fugate, a ranger at Chiricahua National Monument in Arizona, was Jan. 13, 1980, when the 41-year-old went for a hike and disappeared.
Fugate, who had been working in the monument’s visitor center, left the building to hike a park trail and was never seen again.
Although search teams combed the surrounding area extensively multiple times, they found no sign of the missing ranger.
Investigators suspected foul play early on, and a formal missing-person case remains open.
The National Park Service still has a $60,000 reward for information on the case.