Will be in Amsterdam 20-23 Nov 06. Was thinking of taking a day trip to Rotterdam and taking one of these trips. I've checked the Spido website, and it seems there is one on Wed afternoons at 2pm, which would fit in fine. Could someone let me know where these tours start from please?. There is no mention on the website. Also, are these tours popular in late Nov? I wouldn't want to waste time going to Rotterdam, if the tour was cancelled due to insufficient demand.