Planning

Here's the big picture (Google map link: https://goo.gl/maps/zqrAWvMmnwT2):

Dunkirk Sat Aug19 - 8am ferry
8:00 (BST) - 11:00 (CET)
Lunch in Dunkirk?
12:30-16:00 cycling to Ypres (64km, 3.5hr ride @20km/h)

Ypres
Cloth hall + cathedral, Menin Gate,
16:00-17:30 sightseeing Ypres
17:30-18:30 Dinner Ypres

18:30-20:00 Kortrijk (30km, 1.5hr)

Kortrijk  Sat Aug19
68km to (via Oudenaarde) 3hr and 3 climbs (80m, 70m, 80m)

Ghent  Sun Aug20
Castle Gravensteen, St Bavo, St Michael Bridge, Belfry and Cloth Hall
(night) Graslei,
or 67km (Google) to
or 64.6km (Google via Waasmunster) https://goo.gl/maps/aDYb4JKftT12
64.0km (Strava) to

Antwerp Mon Aug21
Market,
104km! to

Rotterdam Tue Aug22
Rotterdam Wed Aug23
100km to

Middelburg Thu Aug24
10km to ferry https://www.westerscheldeferry.nl/
35km to Bruges

Bruges Fri Aug25
50km to Veurne
Veurne to Dunkirk (40km)

Dunkirk Ferry on Sat 26 Aug 8pm

Google map link