The map shows Greece. Map of Greece. The Greek Empire is shaded in green including the cities of Athens, Sparta, and the island of Crete. The Pindus mountains are marked by a triangle. Judging by this map, what is the single most significant characteristic of Greece

The correct answer to this open question is the following.

Unfortunately, you forgot to attach the map. Without it, we do not know what is its content.

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Judging by this map, the single most significant characteristic of Greece is that Greece is bordered by land on one side only. On the other side is the Mediterranean Sea.

The Geography of Ancient Greece made trade to be a difficult activity  

The major difficulty with trade-in in ancient Greece was that mountain ranges made transportation very difficult.

Although trade was very important for the Greeks, its geographical characteristics made it difficult to trade by land. The geography of Greece has many mountain ranges. For instance, the Olympus range, a series of mountains, includes the famous Olympus Mountain, home of the Greek gods in Greek Mythology. Another two mountain ranges in Greece are the Pndus range and the Rhod*pe range. That is why the Greeks had a very good navy, not only for war purposes but also for trade by sea.  

Pachacuti created a highly centralized state and his successors extended the boundaries of the Inca Empire