Fermilab Authorized Personel Only

Fermilab Pi Shaped Power Lines on A-1 and an "Authorized Personel Only" Sign.

Fermi National Accelerator Laboratory (Fermilab), located in Batavia near Chicago, Illinois, is a US Department of Energy national laboratory specializing in high-energy particle physics.
www.fnal.gov/

Photograph taken by Michael Kappel
MichaelKappel.com