Brugge is nice for a one night stop.
What is your exact itinerary and where do you need to fill some spots?

Agree, Brugge.

Paris to Nice to Barcelona is going way out of your way.

Anything in Switzerland, ditto.

If you want the coast, there is the Atlantic coast with towns like Biarritz. That would enable you to also see San Sebastian, a beautiful city with great food.

It doesn't sound like you've put together a more specific itinerary. You might try that before honing in on where do I go.

ok the itinerary starts in London for 3 nights, then to Amsterdam for 2 or 3 nights. After that its either straight to Paris for 4 nights......5 night gap......then Barcelona for 3 nights and finish in Madrid for 4 nights...

So far I have just booked London. Its starts on Sept 15 ending on Oct 7.

So its either stopping at Brussels..then Bruge??.......or something between Paris and Barcelona.

Given my itinerary is mostly (if not all) major cities, adding some countryside would be nice....but not the entire 5 nights i have left.

anyone???? help!!

Eric, last year I did London - Edinburgh - Amsterdam - Brugge as a 2-3 weeks drinking trip with a couple of friends. I found real cheap plane tickets from Edinburgh to Amsterdam.
You could add Paris, Barcelona, and Madrid and complete a nice itinerary, but it depends on how many days you allocate/need to spend in each city, how you travel, etc... in the end what kind of a traveller you are and what you want to do.
I'm going this summer on a two months trip and when fodorites saw my planned itinerary they said I'm crazy. But it does make perfect sense to me.
So, look at the map, research destinations, and come up with something that makes YOU happy.
Planning is very important. For example, in my initial plan I was going to visit the Vatican on August 15. Surprise when I read that it is closed that particular date. So, do your homework.

I think your plan is nearly there and sounds like a good one

i would do

london 5 (then fly to)
amsterdam 3 (then train to)
Brugges 3 (then train to)
Paris 5 (then fly to)
Barcelona 3 (then train to)
Madrid 4

Brugges and Amsterdam are lovely quaint places that i think are definitely worth having and very different to the likes of Barcelona, Paris. London and Madrid which are far bigger,

If you wanted you could take a night from Brugges and Madrid and catch an early train from London to Edinburgh for a two night stay before flying off to Amsterdam. It takes about 4.5 hours giving you a day and a half to explore Edinburgh which is a very walkable compact city.

(u dont need to stop overnight in Brussles but probably need to change trains there on route to Paris, Brugghes is about an hour or so north of it with plenty of trains to Brussels on the half hour i think. In my own inexperience Brussels was definitely not somewhere i personally would recommend as a highlight of Europe for your trip)

london 5 (then train to)
Edinburgh 2 (then fly to)
amsterdam 3 (then train to)
Brugges 2 (then train to)
Paris 5 (then fly to)
Barcelona 3 (then train to)
Madrid 3

I would personally do the first version as a bit more relaxed but the second one is definitely doable to as you have long stops in london and Paris

sorry, just saw your countryside request. If you decide you definitely want to do this then Avignon in beautiful Provenece could be a possibility? But i would stay 4 nights to make worthwhile

You could switch Amsterdam (or Brugges) to go straight to Paris and then fly to Avignon (the eurostar goes there too but would take all day). But trains from Avignon to Barcelona look like they involve changes so would probably reccommend hiring a car when in Avignon, (a) to enjoy the countyside to the max and (b) to drive to Perpignon where you can catch a train to Barcelona (i think)

london 5 (then fly to)
amsterdam or Brugges 3 (then train to)
Paris 5 (then fly to)
Provence 4 (then drive/train to)
Barcelona 3 (then train to)
Madrid 3

Having said that Amsterdam and Brugges are really very nice so if your heart is not set on visiting the coutryside then Amsterdam will be great. If you did fancy this option then worth noting thatou can go straight from london to Brugges via eurostar (quick change in brussels) so would save the need to fly if you went with Brugges rather than Amsterdam.

apologies, the above wasn't very clear when i said

"if you did fancy this option then worth noting thatou can go straight from london to Brugges via eurostar (quick change in brussels) so would save the need to fly if you went with Brugges rather than Amsterdam." i meant the provence option.