Living in Essex we don't normally stop near Calais.
I can heartily recommend Mike's place, Rivervalley guesthouse, as a stepping stone on the way down. Basic but the great price reflects it and Mike is mad on bikes so you will be well looked after. Secure bike parking etc.
http://www.river-valley-guest-house.co.uk/ I always make sure to nip through Luxembourg on the way there to make the ride interesting - as the ride is the Holiday!
I can recommend the A99 road in Austria - simply stunning and lasts for ages! Start at the southern end (Lieserhofen?).
Chris