The Kalamata olive is a large, dark purple olive with a smooth, meaty texture, named after the city of Kalamata in the southern Peloponnese, Greece.

Often used as table olives, they are usually preserved in wine vinegar or olive oil. Typically the term "Kalamata" legally refers to a region of Greece where these olives are grown, however a few countries (those mainly outside the United States and European Union) use the name for such olives grown anywhere, even outside of Greece. Within the EU (and other countries that ratified PDO (protected designation of origin) agreements or similar type law), the name is protected with PDO status, which means in the EU the name can only be used for olives (and olive oil) from the Messinia region of Greece.

Kalamata olives, which cannot be harvested green, must be hand-picked in order to avoid bruising. They are classed as black olives.

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