Summary: It might look a lot like earth, but it's not.
Sticking her head out of the TARDIS, Amy frowned. Far from the alien world she’d expected to see, they could have been in a farmer’s field back on earth. Luxuriant green grass spread out around them, dotted with small yellow flowers, and the sky overhead was blue with a few fleecy white clouds drifting slowly across it.
“Are you sure this isn’t earth?”
The Doctor’s head popped out beside Amy’s.
“Nope, definitely Rinchahan. See?” He pointed. “You don’t get those on earth.”
Several creatures trundled into view, looking a bit like walking bagpipes, busily cropping the grass.