I posted this last year but nobody really cared then.
What with the moon mining change coming this winter I’m sharing it again.
I queried Belts vs Belts, Belts vs Stations, Belts vs Moons (per each system) to find the distance between. Any asteroid belt that is within 16,000km of either another belt, a station, or a moon is listed [here.] (https://docs.google.com/spreadsheets/d/1LKcuPqA3hy_rodtp1inj0qovajnpSxs5rSHE0qTZBPs/edit?usp=sharing) (I chose a conservative grid size)
For example : BJC4-8 VII - Moon 1 is 4,069km away from BJC4-8 VII - Asteroid Belt 1 (according to x,y,z coordinates in CCP’s data dump). With a well placed Refinery structure you could do…stuff.
Please note that I haven’t actually visited 99% of these systems 