Comment by elahd

Verizon, actually. Not the mail tubes specifically, but they own Empire City Subway, a 130 year old company rents out sub-street conduit for telecom. Their tubes are visible when streets are dug up for construction.

https://www.empirecitysubway.com/

https://en.wikipedia.org/wiki/Empire_City_Subway

Looks like their lowest rate (<=2.5" conduit) is $3,660/mile/yr, not including installation, permitting, and city franchising fees. Still interested?