The next downside is whether anyone would use such a tunnel, given that plane travel would be much quicker, probably safer, maybe cheaper (tolls on such a tunne

The next downside is whether anyone would use such a tunnel, given that plane travel would be much quicker, probably safer, maybe cheaper (tolls on such a tunnel plus gas would be quite expensive), and possibly more enjoyable (better views in a plane, it’d probably be depressing and claustrophobic being down under for so long)