To follow up on that last post, I think this is the formula for how wonders generate tourism: Each wonder automatically generates +2 tourism. It then generates a further +1 tourism for every era you are advance beyond the wonder's era. So the Colossus (a classical era wonder) generates +5 tourism per turn in the industrial era. This value is doubled at Computers. It is also doubled for France (so it is quadrupled if France has researched Computers). So if France is in the Information Era and has teched Computers, Stonehenge (an ancient era wonder) would generate +36 tourism per turn. Of course, wonders can also generate further tourism by holding great works. I believe that France's UA does NOT double the tourism output of great works within wonders.