I'm not sure how you can find something appropriate for each city, but you may be able to find some larger glass candle holders and votives cheaply, maybe even put some marbles in them. If the outside glass is a reddish/maroonish color the glow will look really nice and romantic.

You may just have to do place cards with names of the cities on them on the table. I'm not seeing how you can incorporate cities or buildings on every table when people probably won't even know what they are to begin with.

Maybe you could do regional appetizers on each table from that specific country.

Just thought of this, maybe you could find or make little flags of each country/city and use them for the centerpiece.

If you are doing assigned seating, you could put the guests first names in the foreign language of the table on placecards.

I'm not sure exactly how you could do this or if the kids would "get it" but we went to a fabulous fundraiser that used the Orient Express as a theme.

Posters of European cities were placed on the centers of the tables with "train tracks" drawn on the tablecloths leading to to the next table/city.

The tables were long and narrow, maybe 12 to a table, and each table had 3 or maybe 4 candles on them. But the candles were really neat. A plain candle with a small beaded "lamp shade" over it, they look like 20's style lamps.

The walls were covered with sheets strung from wire and the light was projected from the back so it looked like windows, they even had the sound of a train in the background, very faint but there. It was really neat.

Way to much for your needs I'm sure but the notion of a poster of each city being connected to the next table/city would be easy enough...just get your atlas out!

There are so many romantic aspects to the Orient Express. Perhaps if your daughter did some research on it she may get ideas.

How about using picture postcards of the cities to make some kind of arrangement? You might check ebay for that sort of thing.

I'd do photos and framed for the table of Paris, etc.,.

It's too bad she doesn't like flowers since that is one of the first things i think of when I think Paris. The fresh markets are abundant with them.

Watch the movie "An American in Paris" to get inspired.

I was a guest at a retirement party that had a travel theme. Each table was similarly set with a basic cloth and the same place settings, but the tablecloth square topper was a different fabric to go with each place. They used all sorts of different items as centerpieces that they had collected like small antique-looking travel luggage (the make-up case size), binoculars, maps, etc. You could create a different centerpiece at each table to be like a still-life painting of sorts (hats, tea sets, ceramics, mirrors, stacked leather-bound books, fruit [plastic or real], scarves)... pretty much anything laying around the house that has a weathered, antique, or european look to it. Don't forget that friends can be a great resource for stuff to borrow too. You might also mention the dilemma to your daughter and see if she has any ideas. She might come up with something that could be a great jumping off point. (Sigh). Oh sure, now I've got a craving to watch "A Room With A View" again. Good luck!

I think lowspark's postcards idea is brilliant. You can arrange them at different heights, perhaps mixed with that curly, spirally stuff called ting-ting, stuck into a painted styrofoam base to make a really inexpensive but cute centerpiece.

Look for one of those catalogs like orientaltradingco.com (I think their paper catalog is better, or best of all just call them) -- they have tons of cheap stuff on every imaginable theme, and I know they have paper flags. Think outside the box when searching -- like, use "fiesta" to find things that could work for your Madrid table or "carnival" for Paris.
It might be easier if you could get her to expand the theme to "international fantasy" instead of limiting herself to Europe -- then you could also have a tropical island table, a Chinese table, a Japanese table, African, Brazilian, Jamaican, and for that matter New Orleans and NYC, etc. -- then you can start with what you find and choose your cities/countries that way instead of the other way around. Kind of drawing the bullseye around the arrow.