Legolas is able to see Minas Tirith and Mordor from Edoras

‘Verily,’ said Gandalf, now in a loud voice, keen and clear, ‘that way lies our hope, where sits our greatest fear. Doom hangs still on a thread. Yet hope there is still, if we can but stand unconquered for a little while.’

The others too now turned their eyes eastward. Over the sundering leagues of land, far away they gazed to the edge of sight, and hope and fear bore their thoughts still on, beyond dark mountains to the Land of Shadow. Where now was the Ring-bearer? How thin indeed was the thread upon which doom still hung! It seemed to Legolas, as he strained his farseeing eyes, that he caught a glint of white: far away perchance the sun twinkled on a pinnacle of the Tower of Guard. And further still, endlessly remote and yet a present threat, there was a tiny tongue of flame.

The Two Towers, Book Three, Chapter 6: The King of the Golden Hall.