Originally Posted by
HIDDY
I haven't heard any need to book in advance especially in August.
There isn't a lot to see in Colonia so you'll have plenty of time to do the usual walking tour, have a bite to eat and still have time to relax by the water before before getting the 16.30 back. It'll be dark by 6.30ish anyway so no point in waiting for the 20.30.
We'd have gone stir crazy if we waited until that long (i.e,. until 20:30). It was on a late July bitterly cold and windy day. This included walking around the historic area, sat at a cafe, walked some more, hired a taxi to show us around the city on a little tour, back into the central area, sat and had a lovely lunch, and then walked back to the ferry terminal, in time for an early-ish check-in so we could choose some preferable seats.