What went wrong at King’s Cross over Christmas?

There were highly publicised problems and delays at King’s Cross Station over the Christmas period, for the nebulous reasons of “engineering works”. But to their credit, about a fortnight ago, Network Rail published a full report about the disruption, explaining how the carefully planned works overran so badly.

The report goes into a lot of detail, and it’s well worth reading. But if you just want a high-level overview of the major problems, then this summary is the best that I’ve read so far.