Five Wonders of Oregon to See This Summer
Thor's Well, Yachats 
Sitting on the edge of the Oregon coast is what appears to be a gaping sinkhole that never seems to fill despite the unbroken stream of sea water that drains into it. But, Thor's Well as the natural wonder is known, is not bottomless, but it is very dangerous.  
Out'n'About            Treehouse Treesort, Cave Junction
Near the redwood forests of Oregon, secreted away high up in the trees is a city of tree-dwellers. Anyone can join their ranks at this "Treesort", a bed and breakfast where guests sleep in their very own treehouses.
Lava River Cave, Bend 
Head to Central Oregon and explore the longest continuous lava tube in Oregon, which is part of the Newberry National Volcanic Monument. Measuring in at 5,211 feet (1,588 m) in length, the northwestern section of the cave is the longest continuous lava tube in the state of Oregon.
World's Largest Organism, Grant
Known locally as the "Humongous Fungus", the massive networked fungus growing beneath Malheur National Forest may be the largest and oldest life form still active on the planet. This gigantic mushroom has spent centuries eating its way across a huge swath of Oregon.
Portland's Shanghai Tunnels, Portland
From 1850 to 1941, Portland was considered one of the most dangerous ports in the world. It earned the moniker "Forbidden City of the West" due to the Shanghaiing trade and the white slavery that was carried out there. Now you can tour the historic tunnels and learn about the early years of Portland.