Just slightly more on "fixed links", the engineers fancy expression for "bridges and tunnels". As I have commented before, the United States built most of its key links in the hundred years to about 1950, and there has been little left to do since 1950 or so. In Europe, building the key links was a post WWII thing, and most of the key links have been build between 1950 and today. Some of this is due to later industrialization, some is due to the fact that the needed links were longer and harder to build. (Surprisingly little is because links were built, destroyed in the war, and then rebuilt). In any event, Europe's links are just about complete. One or two really big things (Channel tunnel, Great Belt Link (between Denmark and Sweden), have been built recently, and one or two others (Messina Bridge, various tunnels through the Alps) are either under construction or in the later stages of planning). Japan's links are just about complete, too, although the Japanese have found it difficult to stop building, and they are still pointless building bridges and tunnels because the construction industry almost runs the country.

I have visited most of the key bridges and tunnels in the US, most of the big ones in Europe (with the exception of the Great Belt Link), and some of the big ones in Japan. However, if you look at this table of the longest bridges of various types in the world, either existing or under construction, what is impressive is the huge number of bridges in China that are on the list. The Chinese are clearly on an immense infrastructure building boom. (Actually, what would be interesting would be to see where these all are on a map, to see how this collelates with population, economic growth and various other things). In particular, look at the number of large cable stayed bridges in China. In the US or Europe, most bridges this size were built a few years or decades ago using other construction techniques, but in China, they are being bridged at a time when the cable stayed bridge is state of the art. Therefore the dominance of this type in China. I need to go on a tour of China to see some of these. (Of course, what will be really interesting will be to tour China in 50 years, at which point all the cable stayed bridges will have dated, and will be a quaint reminder of the first decade of the 21st century, in the same way that all the steel truss bridges you see in the American midwest are a similar quaint reminder of an earlier time).