Google Sightseeing takes you on tour of the world as seen from satellite, using the free Google Earth program, or Google Maps in your web browser. Each weekday your guides James and Alex present new weird and wonderful sights as suggested by readers.
This is the Tonto Natural Bridge near Payson, AZ - which is less like a natural bridge and more like a natural tunnel.
The creekbed disappears into the 50 metre-high tunnel for around 120 metres - the two entrances you can see in our thumbnails, and the inside of which you can see in numerous online galleries. (I’ve chosen this gallery to link to, because I like the way they’ve gone over the top with arty-farty photoshop filters 
)
Thanks to Jason Creach.
This form will auto-link URLs or you can use simple HTML, <a href="http://googlesightseeing.com">Like this</a>.
Link to specific places either as a Google Maps page or a decimal latitude and longitude written like this: lat/lng:55.949400,-3.200000.
If you've found an unrelated sight that you think should be posted in its own entry then use the suggestion form!
With 144 pages of glossy high-quality satellite photos, the weirdest and best of Google Earth is now available in the…
I took some ground level shots:...”
Believe it or not, but it’s actually the largest natural travertine bridge in the world. I used to love this place as a kid, when it was still privately run. In the last decade or so, Arizona State Parks has acquired the property and has built a bunch of crap, including that god-awful parking lot (on top of the friggin’ bridge, no less). You used to park near the old ranch house and walk down some nice trails towards the bridge, and then, in a moment of discovery, notice what was there. After scrambling down into the canyon, you’d be rewarded with some great swimming holes and tales of indians and bandits that used the area.
Is it the largest natural bridge in the world? There is a very good one in Puentedey, province of Burgos, north of Spain, that seems to be larger. Here is a website to see it: http://www.puentedey.es/. Unfortunately, Google Earth has no good views of this place.
Dang, Alex, you weren’t kidding about the gallery!
Oh, and Ignacio, click on the link at the top of the post that says “natural bridge”.