Paris - If he is a shopper or a person that likes being in the kitchen - absolutely go to E. Dehillerin for kitchen items. It's the place that all French chefs shop. I could have spent days in there.
http://www.e-dehillerin.fr/en/index.php

I would recommend any of the walking tours by
http://www.paris-walks.com/
The guides are English speaking, the tours are around 2 hrs and they are excellent. We've done about 10 of their tours and would do them again in a minute. Very reasonably priced.

When we were on a "see all of Europe in 16 days" kind of tour, Amsterdam was on our agenda. Our guide told us there was an old church we should see after supper one night....well, he took us on a tour of the red light district. That really bothered me....seeing the girls posing in the windows, etc. We could have done without that bit of Amsterdam. Did like the canal boat ride, etc.

Never been to Amsterdam but I think Anne Frank's house is there, or rather the one she lived in before she was taken to the concentration camp.

There's a cool boat ride in Paris, haven't been on it but may this summer. If you go to the link and then click on individual tours, you can see a video of the cruise. Then there's the Seine river cruise, been on that one a long time ago, very nice too.

Then there are the catecombes: http://www.catacombes-de-paris.fr/english.htm

Here is a link that might be useful: St martin canal

Sorry, gave you the wrong link, here it is and the videos should be on this first page.

Here is a link that might be useful: video St Martin canal

My DH has been to Amsterdam and he highly recommends going to see the Anne Frank house. Incredible history and very humbling.
I was in Paris 20 years ago, and my favorite thing to do there was walk through Montmartre visiting all the local artists. We bought a pencil sketch of the Arch de Triomphe which still hangs in my hallway. If he has time, make sure to see the major attractions, too.

I loved the boat trip on the canals in Amsterdam. Been years since I was there. Sorry, nothing comes to mind, to recommend.

Moni

A trip to the Hague is in order.

We were there many years ago and loved the boat trip in the canals of Amsterdam. We found the people very friendly and most all spoke English. It was a lovely city and I'm sure it still is. There are so many things to see in Paris and you don't have to travel far to see them, as I remember. My DH went to the top of the Arc 'de Triumph for a birds eye view of the city, I don't know whether you can still do that or not. It was years ago and we were young, but I remember both cities fondly!

Suggestions for Paris:

If your DH is a gardener, April or May should be a great month to go see Giverny, Monet's gardens outside of Paris. It's a short train ride out of town, with a shuttle bus to the gardens. Probably a half-day trip on a Saturday or Sunday.

Also, I'd skip the Louvre (I assume he'll be working during that week and hence does not have everyday to see everything), in favor of the Musee D'Orsay, where most of the 19th and early 20th century art is located.

Just walking around city center is such a treat -- stop for coffee or a glass of wine at an outdoor cafe and watch the world go by. If the weather gets hot, I highly recommend getting a to-die-for sorbet at Bertillon. The ice cream there is good, but the sorbets are the main attraction.

On Sundays there is a flower/bird market near Ile de la Cite Metro stop - it's free and it's a pretty cool sight.

The Louvre should not be missed - it's free on Mondays (and very crowded)! Also at the other end of the Tuileries is the Musee D'Orangerie where you'll find Monet's water lillies in their own special room.
Paris is a great city - and the Metro is easy to use - tell Claude to buy a carnet of tickets (10 in a carnet) - it's much cheaper than buying them singly.

He MUST eat a Dutch pancake. If he has time, a day or half-day trainride around the country is wonderful. Dutch trains are ON TIME, clean & display Dutch art.

Here is a link that might be useful: Countryside of Holland

I'm going off to bed now but I have a few ideas on and off the beaten path. I'll make a list tomorrow for you and kathsgrdn.

Karen

Ahhhh, Paris! I LOVED it and think everyone in the world should visit! OK, DEFINATELY The Louve, Norte Dame, Eiffel tower, Champs-Elysees, Basilique du Sacré CÂur, Jardin du Luxembourgý, and just wander around and buy crepes at the sidewalk stands, pop into a little restaraunt for whatever their special is for lunch, grab something delicious looking at a bakety you walk by, and DRINK WINE!

Ok, I found something even better than just a list of things to do. I found the address for the office of tourism in Paris. Everything you'll need is on this site and it's in english :)

Here is a link that might be useful: office of tourism in Paris

When I was in Amsterdam I enjoyed the wooden shoe factory (I still have my shoes) and the cheese factories were very good. I thought the Red Light District was a hoot (I was in my 20s then). Only spent a couple of days in Paris in 1970 and don't remember the names of any places.

We were in Amsterdam 2 years ago and loved it.

He might want to go to the Rijksmuseum which has many of the Dutch masters work.

He should check the Keukenhof Garden to see if the tulips are in bloom--if so, a visit would be a "must." It's an indescribably beautiful floral display.

He could also visit the flower auction in Aalsmeer. It's world-famous, and tourists walk on a catwalk above all the action. It's very interesting.

Tell him to watch out for bikes and cars as pedestrians there are not as well protected as here. The Dutch are serious bike riders, and when they are riding, they are going somewhere not just out for a leisurely pedal!

If he likes models, Madurodam is a very large miniature version of many of the points of interest in Holland. It's quite amazing.

English is pretty widely spoken. Wish you could go too.

We also went to the Red Light District, and I'm glad I saw it. We just walked through with a group. The "industry" is highly regulated in Holland.

I second the idea of Montmartre. It's easily reached by the Metro. If you like art, you'd love it there. You can see the house where Picasso once lived.