This is a really neat map of the PA coal fields and collieries from 1898.
https://www.davidrumsey.com/luna/servlet/workspace/handleMediaPlayer;JSESSIONID=64699d50-542d-4f9d-940d-dc9e82ab74d8?qvq=&trs=&mi=&lunaMediaId=RUMSEY~8~1~237664~5511252