[nradov]

Traditionally VCs centered around Sand Hill Road wanted all of their portfolio companies within easy driving distance so that they could attend at least two in-person meetings per day. Obviously that requirement has started to break down.

Proximity to universities has also been a key factor. Silicon Valley has two world-class research universities plus numerous second and third tier schools nearby to act as sources for new technologies for commercialization.

In the early days proximity to Moffett Field and NASA Ames also helped to launch the Silicon Valley innovation engine. There was a lot of cross pollination of people and ideas with military and aerospace.