Google’s “Subscribed Links” is a cool new feature for Google Search which, when you’re logged into your Google account, allows you to subscribe to dynamic search results from your favorite websites.

We’re created a Subscribed Links feed for Google Sightseeing, which will give you 3 recent posts any time you search for a country name. You can view example results and subscribe on our profile page.

The Stanford Linear Accelerator Center (SLAC) in California is funded by the US Department of Energy but operated by Stanford University. The SLAC has a 3km long underground linear accelerator which is the longest linear accelerator in the world and claimed to be the world’s straightest object. The building above ground on top of the accelerator, the “klystron gallery”, is the longest building in the United States.

The Advanced Photon Source (APS) at Argonne National Laboratory in Illinois is another US based lab with a linear accelerator but this one uses a Synchrotron. A synchrotron is a circular accelerator that uses a magnetic field to turn the particles and an electric field to accelerate them. By careful tuning of these two fields particles can be accelerated to 99.999999% of the speed of light. Once particles get up to these speeds the experments can begin. The super accelerated particles are shoved through things, bent with mirrors and have other particles injected into the steam to see what happens.

These two circles that look like a sideways eight are the Tevatron at the Fermi National Accelerator Laboratory in Illinois and make up the world’s highest-energy particle accelerator. Four miles in circumference, the Tevatron is housed in a tunnel about 30 feet below the big ring you see in the aerial view. The particles complete the four-mile course nearly 50 thousand times a second. Damn, that is fast.

The other big player in particle accelerators in CERN, the European Organization for Nuclear Research, the world’s largest physics laboratory. CERN is located on the border between France and Switzerland and is otherwise known as the birth place of that thing called the World Wide Web. CERN have numerous particle accelerators but the biggest is the Large Hadron Collider. The LHC is currently under construction in tunnels that used to house the Large Electron-Positron Collider which ran from 1989 to 2000. This tunnel is 27km in length and 100 metres underground! It’s like something out of Half-Life! Unfortunately there isn’t very much to see from the air, the LHC is located somewhere in the area between Geneava airport and the Jura mountains to the North. I’ve been staring at the imagery for a while and I can’t make out any trace of it on the surface. Can you?

I’m sure there are many more accelerators out there to see but my head was starting to hurt from reading about particle physics. Feel free to post your particle physics related finds as comments on this post!

Thanks: Scott Lawson, dan, Matt, Jason, Rahul Karnik, David, joe, Foo Bar, Matt, Tom, Ilia Baldine, Douglas Boberg, Fred, Dave D, Brian Potter, Steve Abrahamson, Thomas Wade, Laurence Dorazio, Daryl Achilles, Tony Scislaw, Marc Armstrong, Tyler Stevenson, Joe, Luistxo Fernandez, Janx Spirit, David Drexler, David Drexler, Matt W., Matthew, Rodrigo, Joe, Jochen, Matthew Sz., Williamckley, Drew DeMott, Michael Lehet, Hubert Grzywacz, Bjørnven, Thomas, J Foote, Brad Lauster, Dalvenjah FoxFire, Robert Bogdon, cjw, Parker, Jim Duncan, Steve Bryson, Jeffrey Deane, Ryan Means, Benjamin, Jason Harris, David Drexler, Bobllingson, Lennie Stovel, punk floyd, Jason, SFuller and Sounil Yu.

One of our readers, Morgan, lives in Chappaqua, New York, and he’d heard that Bill Clinton (the 42nd President of the United States) lives here too. So Morgan took a little wander with Google Maps, and when he found a house with three black secret service cars out the back, he was pretty sure he’d found the right place

Thanks to the resourceful Morgan.

Although not as famous as the nearby Stonehenge the henge of Avebury is larger and older; dating back to around 5000 years ago. The standing stones are arranged in a circle with a 400m diameter, on a raised piece of land which has a deep external ditch, and surrounds the tiny village of the same name.

It is one of the largest Neolithic monuments in Europe but what’s really cool about Avebury is that, unlike Stonehenge, you can walk right up to and around the stones. In fact, in a move that would probably have upset those who assembled the stone circle, the A351 road cuts straight through the middle.

There’s even more megaliths extending to the West and South in two “avenues” and you can follow the southward avenue down to the Sanctury, where another stone circle once stood. At one time there were around 600 megaliths making up the stone circles and avenues.

Thanks: Ben Moore & Dee

So what are we looking at here? Well, it’s clearly a bus about to crash into a Roman Amphitheatre. Duh.

This is the second largest city in Bulgaria, Plovdiv, which is built around 7 hills. Back in the 70s they were digging up one of these hills in order to extend a major road and unearthed this ancient Roman Theatre. Rather than just plowing on, the road was relocated into a tunnel under the hill. The Theatre was preserved and today is regularly used for concerts and performances. (Ground level photo).

Thanks: Georgi Petrov