Last week my plan to visit New Zealand in 2017 was scrapped when I snagged an incredible price on flights to Amsterdam. So now, I have no knowledge of the area, and have never been, but I have 10 days (excluding travel) to plan for! I just don't know where to begin.
Based on some initial searching, it appears we'd want to spend about 2-3 days in Amsterdam. I think I'd like to see Munich and area castles, and spend some time in the Rhine valley. I don't know if the Black Forest would be possible, but I'm interested in that.
I've thought about getting a flight from Amsterdam to Munich (to save time on travel) and then work our way back to Amsterdam by rail, stopping in Frankfurt and maybe Cologne/Dusseldorf area. I really don't have any concept on how much time each of these would take. I'm looking for ideas that will help me research and piece together a plan. Or suggestions on cannot miss stops. I think we'll have roughly 7 days for Germany.
Not opposed to renting a car, but we're interested in avoiding it.
Travel dates: April 27-May 9
About us: 32 year old couple
Interests: outdoors/moderate hiking, food, breweries/wineries. Not hugely into art or history, but we certainly can appreciate those with significant historical value. We love taking pictures and I'm looking forward to seeing some castles. I like wondering in and out of shops (he doesn't

)
Recent loved trips: Yellowstone National Park, Napa Valley, Kentucky Bourbon Trail
All help and ideas are appreciated! Thanks!