A popular hike in southern Utah that’s known for such stunning sand dunes that the Bureau of Land Management holds a lottery to issue visitor permits has claimed the lives of three people in higher-than-usual July temperatures.

The third victim died this week in the wilderness area known as The Wave when she and her husband got lost on the unmarked trails. The 27-year-old from Mesa, Arizona was hiking with her husband to celebrate their fifth wedding anniversary. When Elisabeth Ann Berval started suffering from heat exhaustion, her husband went to get help. By the time he returned, she was in cardiac arrest.

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“Hiking in Utah, I’ve come across rattlesnakes, mountain lions, bears … And what scares me the most is actually dehydration and heat,” wilderness instructor Adam Provance told an ABC affiliate.

Hikers must watch a 17-minute safety video before setting out. A headache is often the first symptom of heat exhaustion, Provance said.

“As soon as you, or anyone in the party feels that way — stop,” said Provance. “If possible, find shade, sit down, rest and drink fluids.”

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Earlier this month, 69-year-old Patricia Wahli and 70-year-old Ulrich Wahli died at The Wave when temperatures rose over 100 degrees.

“This is a difficult time of year to be hiking in the Wire Pass area of Kane County,” Kane County sheriff’s Sgt. Alan Alldredge told The Salt Lake Tribune. “If you must hike, it is best to do it early in the morning, and make sure you have enough water and supplies.”

Photo: A rock formation known as The Wave in Utah’s Coyote Buttes wilderness area. Credit: Getty Images