One example is that when I was moving, existing friends from the old city gave me a lot of tips of things to get involved in, i.e. there was a run club in a cer

One example is that when I was moving, existing friends from the old city gave me a lot of tips of things to get involved in, i.e. there was a run club in a certain neighborhood or whatever. Otherwise, previous friends knew people and put me in touch. And finally there were 1-2 people who had also moved to the same city at some point, making it easy to plug into their networks