LHR is very hit-and-miss.
T1 and T2 are god-awful. Thank God they're tearing down T2.
T3 is alright, once you make your way through shopping purgatory.
I never minded T4.
T5 is beautiful, save the security.
The worst airport I've ever visited in Europe is LIN (Milan Linate). Dreadful in every sense.
How about a thread for the
best airport in Europe? Or didn't we have one of these recently? My memory fails me.