Rode from Calais to Kandersteg in Switzerland, to meet up with some mates & go climbing back in 1991. Plodded along over 4 weeks, travelling light. Had a wail of a time, met loads of nice people along the way, inc stopping & sightseeing in various small tows & cities. Not sure how far, but I was kind of meandering along.
In Bern I met a lovely retired couple who were cycling round the world. They'd started from Australia 18mths earlier, and had just started to need to replace worn out kit, luckily they'd just hit europe. (They were in their mid 50's)