The second part of the Book of Isaiah sometimes called Oracles against the Nations (OAN). In these chapters we find 10 speeches of Yahweh directed to different countries/territories.

1. Ch. 13 - 14 - Babylon

2. Ch. 15 - 16 - Moab

3. Ch. 17 - Damask (Syria) 

4. Ch. 18 - 20 - Cush (Ethiopia) and Egypt    

5. Ch. 21:1-10 - Wilderness of the sea  

6. Ch. 21:11-12 - Dumah (possible word-play on Edom)

7. Ch. 21:13-17 - Arabia 

8. Ch. 22 - the valley of vision 

9. Ch. 23 - Tyre 

10. Ch. 24 - 27 - Re-creation of the whole earth. 

Sometimes it is difficult to identify the addressee. For example, 21:1-10 can be a return to Babylon (cp. v. 9). 

Also it is interesting to notice the structure of the last unit (ch. 24 - 27):

A. 24:1-9 - judgement over land 

  B. 24-10 - 25:5 - judgement over city 

    C. 25:6-12 - judgement and restoration of the Mountain

  B'. 26:1-21 - restored city 

A'. 27:1-11 - restoration of the land 

Conclusion: 27:12-13 - restoration of the land, Jerusalem and the mountain.