Hey, you've got a bike, nothing can stop you
.
Well, except British drivers. Still, cycle to Harwich (~250 miles, should take about two days if you gun it for 10-12 hours a day), take the ferry to Dutchyland, and enjoy a bike-friendly country. Go through Amsterdam if you're feeling like taking risks (protip: avoid native cyclists, tram tracks, and tourists not realizing where the sidewalk ends and the bike lanes start).