Subang/Sepang - Kuala Lumpur 1998
And what about Sungai Besi / Simpang, its predecessor?
I totally agree (and have said so earlier in this thread) that it would be difficult to imagine LHR closing. However, in respect to the "hub" thread, how many of the other airports on your list had substantial surface rail access at the time of closure? This would make the existing LHR site more attractive to developers, but they'd still have the problem of what to do with the terminals. There are examples of station sheds that have been re-used - e.g. Manchester GMEX (or Central), or Orsay in Paris. Why not - big space, nice roof, just block each end and adapt. What is the alternative use for long corridors, zones blocked off by security measures and jetways?
Silver, I put it to you that your notion of the LHR site being the basis of your island airport is even more of a fantasy than the airport itself. I don't doubt that the site could be redeveloped, if someone taps Justine Greening on the shoulder and tells her HS2 needs to enable a fast link to the new airport and it also needs to link back to the places currently relying on LHR.
Right now though, given the density of the site (1000ha compared to 14,000ha for DEN), it cannot possibly be worth more closed than it is open.