Best single travel guide per area

[simonpickard]

So if you were to buy one guide, one book for an area what would it be?

Eg..

Caribbean: Fodor's Caribbean (2013).

Just wondering what the best guides are per world area...

Regards,
Simon

[Teknav]

Frommer's Caribbean, Frommer's South Pacific, etc...

[rebel heart]

Southern California / Channel Islands - Fagan
Mexico / Baja - Rains
Central America (Pacific Side, excluding Costa Rica and Panama): the couple who's name eludes me that has them as PDF's on their website.