Explore Chicago Collections
https://explore.chicagocollections.org/records/?f2-types=Digital+Images&f3-topics=Natural+%26+Built+Environments%3A%3ARailways&f7-institutions=Chicago+History+Museum&f6-topics=Work%3A%3ABusiness&f5-topics=Work%3A%3ABusiness&f1-neighborhoods=Loop&f4-neighborhoods=Loop&sort=title