I live in the Southern part of The Netherlands but I quite like an area called Friesland in the very North of the country. A different language to Dutch is spoken here. We once spent a cycling holiday in that area and took the ferry across to one of the Islands (Ameland) and cycled around. The region is not too built up and we cycled for miles along canals, saw an old farmer wearing clogs while working in the fields, visited a working windmill and bought organic mueseli. There's even an option to do some waddy (mud) walking across to the islands with a qualified guide, but the tides weren't in our favour.
How are you planning to travel around ? A special train ticket is available at that time of the year. It costs about 99NLG (50 US Dollars) in total for 3 days of unlimited train travel in The Netherlands for 3 days out of a period of 10 days. On this ticket you can just hop on and off wherever you like.
What kind of things to you like to see/visit while travel then perhaps I can be more specific.