"You find the weirdest stuff" – annual Half Dome clean up reveals the crazy things hikers leave behind

One man's trash, as they say, is another man's treasure, and there was plenty of treasure to be collected at this year's clean up on Half Dome.

Tens of thousands of hikers climb the 8,842-foot granite monolith in Yosemite National Park each year via a steep route using a system of cables that are bolted into the rock. While all should be packing out any trash they generate over the 10 - 12-hour hike, it's no wonder that a few items get dropped along the way. You might not be surprised to learn of the odd stray glove or mislaid pair of sunglasses as hikers get tired during the the challenging hike, but the riches left behind this year might have you scratching your head a little.

To keep the area tidy for future hikers and local wildlife, volunteers and rangers gather each fall to pick up trash and collect lost items. This year's event took place last Saturday and, according to an article in the San Francisco Chronicle, entailed a crew of 1,500 people who descended on the cliff, some bushwhacking their way up and others rapelling, to harvest five 145-liter haul bags full of loot.

This year's event turned up the following items:

• 200lbs of reusable water bottles

• Hiking shoes

• Hats and hiking gloves

• Credit cards

• GoPros

• One can of bear spray

• One satellite GPS tracker

As you can see, some of these items seem absolutely crucial to their owner (shoes) while many are just downright expensive. In one happy ending, a cracked phone was reunited with its owner after it was discovered to still be functioning. The clean up mission was part of a larger, five-day Yosemite Facelift program organized by the Yosemite Climbing Association, which yielded 10,000 lbs of trash.

How to 'leave no trace'

The principles of 'leave no trace' need to be reinforced now more than ever. While humanity is becoming increasingly aware of the urgent need to protect the planet, more and more of us are seeking out the wild places in search of mindfulness, escapism and adventure.

Whenever you venture into the wild, you should plan ahead to pack out everything you bring with you, avoid fragile ecologies and minimize your fire risk. Learn more in our article on how to ‘leave no trace’ when pitching or hiking in the backcountry.

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