Yggdrasill is the greatest ash-tree in the world. Three roots extend to three wells: Urðarbrunnr among the norns, Hvergelmir in Niflheimr, and Mímisbrunnr. The eagle, Níðhöggr, Ratatoskr, and four stags inhabit the tree.
Askr Yggdrasils, hann er mestr ok beztr allra trjá. Limar hans breiðast um alla veröldu ok standa yfir himni. Þrjár rætr trésins halda því upp ok standa afar vítt. Ein er meðal Ása, önnur þar er hrímþursar byggja, þriðja yfir Niflheimi.
The ash Yggdrasill is the greatest and best of all trees. Its branches spread out over the whole world and stand above the heavens. Three roots hold the tree up and extend very far apart. One is among the Æsir, another where the frost-giants dwell, the third above Niflheimr.
Orn einn sitr í limum asksins ok er hann mjök fróðr. En í milli augna honum sitr haukr er Veðrfölnir heitir. Íkorni er heitir Ratatoskr renn upp ok niðr eptir askinni ok berr öfundarorð milli arnarins ok Níðhöggs. Fjórir hjörtar renna í limum asksins ok bíta barr.
An eagle sits in the branches of the ash and it is very wise. Between its eyes sits a hawk called Veðrfölnir. A squirrel called Ratatoskr runs up and down along the ash, carrying words of strife between the eagle and Níðhöggr. Four stags run in the branches of the ash and bite the foliage.
Eddic quotations
Ratatoskr heitir íkorni er renna skal aðr um ask Yggdrasils; hann skal arnar orð ofan bera en segja Níðhögg neðan.
Ratatoskr is the squirrel that shall run down along the ash Yggdrasill; it shall carry the eagle's words from above and tell Níðhöggr below.