Sentence:  Afghanistan is a <WSD>sargasso</WSD> of wrecks from earlier civilizations; buried in its earth are hordes of Greek coins, Aramaic inscriptions, Saljuq mosques, and Mazdakite fire temples, flaking away in their own dust, forgotten in valleys where the local villagers carry away their bricks for cattle folds. 
Meaning of the word marked with <WSD> tags:  "Also" '''(Sargasso)''': a confused, tangled mass or situation.