Already booked the Anne Frank House as I have already been told this is something that needs to be booked.
Our preferred mode for holiday is to be pretty relaxed and decide on each day as it comes whether we want an active day, a cultural day or a chill day of not much. What I don't like is deciding that a particular museum or attraction looks great, only to find that I needed to book 6 weeks ago and you can't really just rock up. If you know Amsterdam well, are there any unmissable attractions that get fully booked if you don't plan ahead?