Sentence:  This is not the case, however, because it is protected from the summer monsoon in the southwest by the Island of Sumatra, and from the winter monsoon in the northeast by the overhang of the peninsula of Cà Mau, the <WSD>extreme point</WSD> of the Indochinese Peninsula, a set of circumstances whose effect on alluvial deposits along the coasts has already been mentioned. 
Meaning of the word marked with <WSD> tags:  A point that is physically located farthest in the direction of the edge of something.