The warehouse walls around her were impossibly tall, the ceiling looked kilometers high.

He seemed impossibly tall as he stood over her.

"Too bad about your friends," said the pilot as they headed the dragonfly away from the river and into the forest of impossibly tall trees.

He stood over me, impossibly tall from this angle.

She was on a rocky ledge near the summit of what appeared to be an impossibly tall mountain.

They looked like impossibly tall skyscrapers, a ghost city on the plains.

He stood up and walked away, an impossibly tall man.

The figure before her had become Roger again, impossibly tall and cruel.

The city lies in the shadow of an impossibly tall and narrow spire.

Either of these would be a challenge by itself, but to do both at once seems an impossibly tall order.