I did cycle to Amsterdam many years ago. It was meant to be a week cycling around France, Belgium, Germany & the Netherlands but once I got to Amsterdam the time just kind of disappeared until I only had time to cycle back to the ferry in France 😀
I did not encounter any hills but the ride up the coast & inland was not boring to me. I like the fantastic cycle network in the Netherlands (not so good in Belgium & I now hate cobbles with a passion). The coast was very picturesque, I found all the dams & bridges quite interesting and the odd ferry ride gave me an excuse to take a rest & enjoy the sea breeze. The sea breeze was not enjoyed when cycling into it though. Riding along the canals was nice too.
Thinking about it I loved the whole trip, pretty much everyone I met was very friendly & the campsite in Amsterdam was a lot of fun. Why am I sat here at work when I could be lazing in Amsterdam for the whole summer? Maybe I had a little too much weed while I was there…..