Flights:
Most airlines will fly to any major city in Europe, via whatever hub they use.
Check with your travel agent or airline about carrying bikes or other sporting equipment. Some airlines have extra fees. I have carried kayaks, bikes and skis all over the place with no fuss or damage on any occasion.
This time it was Thai and Lufthansa. The travel agent said Lufthansa would charge extra, but they didn’t, and their chap at Venice gave excellent service. (Pity about the leg room in economy, though).
Bike facts.
There are oodles of organised cycling tours in Europe. We met people on them and some felt hemmed in. We did it all ourselves — looked at the map and just went.
Our bikes: Giant AT840, 24-speed gears. Excellent, robust. But make sure you have extra strength back wheels, either 36 spokes or if 32-spoke double strength rims. Make sure the pannier-rack attaches securely to the frame and the panniers come on and off the rack easily.
Take plastic bags for waterproofing.
Practice packing the bike into a frame-only-size package for trains.
Take polypropylene undies and t-shirts (long and short sleeves); nylon bike shorts and longs; polartec jumper; Gortex coat. They dry quickly overnight so you need fewer clothes. Don’t take cotton or wool.
Buy (northern hemisphere) compass and maps in Europe.
Then halve your load and double your money.