Operational experience with HERA

The electron-proton collider HERA (Hadron Electron Ring Accelerator) at DESY will conclude operations at the end of June 2007 after 16 successful years. An upgrade of the interaction regions in the year 2001 increased the luminosity of HERA by a factor of 2.7 resulting in a peak value of 5.1 ldr 10
³¹
cm
^-2
s
^-1
. For a special experiment, HERA has been operated for the last two months of operation with a reduced proton energy of 460 GeV and 575 GeV. An overview of the accelerator physics and operational challenges, the performance over the last years, the continuous efforts to upgrade and improve the accelerator and an assessment of reliability and availability issues of HERA will be presented.