I don't remember how many files, but typically these geophysical recordings clock in at 10-30 GB. What I do remember, though, was the total transfer size: 4TB. It was kind of like a bunch of .segd, and they were stored in this server cluster that was mounted in a shipping container for easy transport and lifting onboard survey ships. Some geophysics processors needed it on the other side of the world. There were nobody physically heading in the same direction as the transfer, so we figured it would just be easier to rsync it over 4G. It took a little over a week to transfer.

Normally when we have transfers of a substantial size going far, we ship it on LTO. For short distance transfers we usually run a fiber, and I have no idea how big the largest transfer job has been that way. Must be in the hundreds of TB. The entire cluster is 1.2PB, bit I can't recall ever having to transfer everything in one go, as the receiving end usually has a lot less space.