europe travel recommendations  

The other day I traveled out of Paris to visit the Villa Savoye at Poissy.
It had been raining most of the day; when I arrived at the house, the sun had just emerged through the clouds. Being on the roof terrace; listening to the rustle of the trees in the tranquility of the grounds, as the sun shone brightly on the beautiful, clean white lines of this timeless modernist masterpiece - a moment I won't forget anytime soon. Sublime!
I am now in the Netherlands and going to go eastwards. I'm wondering if there are any other must-see houses, buildings or museums in this country. In Amsterdam there is a Rietveld designed cafe in the middle of the park, and I will take a train to Utrecht to see the Rietveld Schroder House. I have recently left Brussels, I understand it has a lot of art nouveau stuff but there was nothing in particular that I understood to be worth a visit. The people at the tourist information centre were awful.
I will be travelling to Germany in a few days, and suspect you would suggest I stop off in Weimar for the Bauhaus, although I will be spending most of my time in Berlin. Please let me know if you have any further recommendations for Germany and the Netherlands for modernist architecture (and any museums I may not have heard of?) Also do you know any reputable architectural tours guide/groups in these countries?
Thank you all so much - hope the sun is shining where you are