[genxy]

I am referring to cross-zone within in the same region, so like us-central1-a to us-central1-b. These are building to building and often never cross public land.

[sillysaurusx]

Oh, yes! I forgot entirely about that case. You're right, egress traffic is charged there too.

Are the datacenters really located so close together? I assumed they weren't within walking distance of each other.

[coredog64]

Correct, they're close in the sense of country-scale geography but physically spaced to avoid specific issues like location on a flood plain.