Zurich is a tenth the size of silicon valley by population though, and it is a big financial centre too. There are other comparable tech-specific places, like Sophia Antipolis, Toulouse.
By github usage, which seems a decent proxy [1], London is second after San Francisco, followed by Paris, and Berlin is only 7 (much smaller city though, so density could be higher).
By github usage, which seems a decent proxy [1], London is second after San Francisco, followed by Paris, and Berlin is only 7 (much smaller city though, so density could be higher).
[1] http://www.itworld.com/cloud-computing/376551/where-world-ar...