They have three tunnels, a linear one, a small loop and a big loop. Over the years the same tunnels get re-used for different experiments. The LHC is in the big loop but it may also be in the other ones, not sure. Basically, the actual tunnels are around for decades but the coliders within them change far more regularly.
Some of the older accelerators will be used as feeds for the LHC. What I was thinking was that if the Proton Synchrotron (say) was being closed down now for experiments then it would mean that it was close to being ready to begin feeding the LHC. Its been a while though since I've read up on how it all will work!
lhc-machine-outreach.web.cern.ch/lhc-machine-outreach/
is a good place to start reading about it.
  