Our most iconic bridges can be categorized in two basic types:
Here is the scenario in question:
There is a straightforward (as in radiating out in cardinal directions) network of bridges that connect city to city in the whole of Europe (can't think of a continent with a flatter enough terrain to start.) Each bridge is 200 feet wide and 200 above street level, enough for four railroads, 18 traffic lanes and four pedestrian walks. Per 6,000 feet stood a massive stone-and-concrete tower 1,125 feet tall. Above city grounds, the towers would double as apartment complexes.
Using the detail listed above, which type would better suit this kind of challenge, suspension or cantilever?