We’re both science nerds and we really wanted to see the particle accelerators at CERN in Geneva. They do free guided tours, but they have very limited numbers of tickets that get snapped up very quickly. The tickets are released in tranches and for several desperate mornings, I got up extra early. It wasn’t until the last tranche that was released only 3 days before that I got us in. Phew!
The tours are hosted by the scientists that actually work on site. You aren’t getting canned spiel, they really know what they are talking about and are happy to chat. There are two main areas that are on the tour. The first area is of the Synchrocyclotron, which was first run in 1957. It’s an impressive piece of machinery, with a very industrial feel. There were lots of huge bolts, large dials and adjustment wheels. Particles were accelerated around a horizontal circular chamber inside the machine that was about 3m across and could manage a maximum particle energy of 0.6 GeV. The machine was in use for three decades before it was decommissioned. It was used to make many discoveries in particle physics. It is now a historic piece, and images and animations are projected on to it to explain what all the parts are and how it works. It was geekily fascinating.
Synchrocyclotron 
Fine adjustment tools
The other half of the tour was for the ATLAS detector on the Large Hadron Collider. The LHC is the current particle accelerator loop that is used at CERN. It is currently the most powerful accelerator in the world, with a main loop of 27km (compared to the few metres of the Synchrocyclotron) which is buried roughly 100m underground and can manage a maximum particle collision energy of 6,500 GeV (so about ten thousand times more than the Synchrocyclotron). Instead of hitting particles into a target, the LHC can send two beams of particles around in opposite directions and collide them at a chosen point. On the LHC loop, there are several detectors. The most famous one is the ATLAS detector, which is where the Higgs Boson was discovered.
ATLAS building with a mural of the detector 
Control room 
Example of one of the 12000 magnet units used in the LHC loop 
Nerdy souvenir
Inside the ATLAS building, there was something extra nerdy… a scale Lego model of the ATLAS detector, with one of the minifigs on a plinth signed by Peter Higgs.
Lego scale model of the ATLAS detector 
Peter Higgs minifig
If you weren’t lucky/persistent enough to get tickets for the guided tour, there’s still a couple of hours of other features to see. Well worth the visit.
A gift from the Swiss government 
Unknown piece of scientific detection equipment – very steampunk!
We then retired to a Carrefour carpark for the night. We are getting much more confident at sleeping in random carparks!