I've seen modified shotguns firing a grappling hook to the other side of a canyon. No lie.

Couldn't find that video, but rescue guys demo their shotgun method here. They only get a max 200', but the bridge builders were getting a lot farther.

And yes, I've tried both a broken brick on a string and a recurve bow to get a line 24' across my little swamp pond. :) Just just need one, thin string to get started.