While national parks are home to some of the most stunning views of untouched nature the United States has to offer, there are also countless dangers (in some cases, even fatal ones) that can await travelers who either disregard safety warnings or accidentally wander off trail.

At the start of June, an 83-year-old woman visiting Yellowstone National Park from South Carolina was gored by a bison who snuck up behind her and “lifted her about a foot off the ground with its horns.”

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Amid several incidents in which visitors have stepped into streams they thought looked mild and got caught up in the current over the last month, Sequoia National Park in central California sent out a “river safety advisory” urging visitors to exercise caution before wading in.

That river might look refreshing but watch out for ‘swift water and slick granite rocks,’ says NPS

“As the summer season heats up, park officials advise visitors to exercise heightened caution around the park’s rivers due to hazardous conditions,” the National Park Service (NPS) wrote in a statement sent out on June 1. “Recent incidents have highlighted the dangers present in these areas. In the past week alone, two swift water rescues have already occurred at the Marble Fork of the Kaweah River. Park officials stress the importance of staying away from rivers, which pose significant risks, specifically due to swift water and slick granite rocks.”

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In both of these incidents, visitors who consider themselves experienced swimmers were swept away in fast-moving water. While both people were pulled out of the water to safety by park rangers, the NPS issued the advisory out of concern that such situations will become more common as the summer rolls on and visitors turn to any streams they come across during a hike as a respite from the heat.

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Headed to Sequoia National Park this summer? Here are some better places to swim

While swimming is not banned, the official advice is to “stay away from rivers” as the ones in Sequoia have “strong currents” and “extremely slippery rocks” that can pose a slipping danger even to someone who is just standing there to look. Lakes such as Sequoia, Pear, Hume and Heather are better-suited for swimming while Paradise Creek Trailhead is a two-mile hike that ends in natural pools and waterfalls in which one can take a dip. As there are no parking spots and the area can only be accessed by hike, many visitors love the ability to swim in remote nature.

For an area with more amenities such as toilets and parking, there is also the Hume Lake Day Use Area. Attracting both swimmers and those looking to do water sports, it is by far the largest and most popular swimming area in the park.

“We want everyone to have a safe and enjoyable experience at Sequoia National Park,” Deputy Chief Ranger Dave Fox said in a statement. “By staying out of the rivers and maintaining a safe distance from the riverbank, visitors can prevent life-threatening accidents and ensure a fun visit for all.”

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