Kastania Καστάνια
Community
Kastania
Coordinates: 36°50′31″N 22°24′00″E / 36.842°N 22.400°E / 36.842; 22.400
Country	Greece
Administrative region	Peloponnese
Regional unit	Laconia
Municipality	East Mani
Municipal unit	Sminos
Population  (2021)[1]
• Community	55
Time zone	UTC+2 (EET)
• Summer (DST)	UTC+3 (EEST)

Kastania (Greek: Καστάνια) is a village on the Mani Peninsula of Laconia in Greece. An independent community since 1912, it became part of the municipality of Sminos in 1997, which in turn became part of the municipality of East Mani in 2010.^[2]

Kastania is 28 km northwestern of Gytheio at the southeastern slopes of mount Taygetos. The village is also named locally Kastanitza (Greek: Καστανίτζα) or Mikri Kastania (Greek: Μικρή Καστάνια).^[3] Within the village is the historic Church of the Metamorphosis. At the village entrance is an impressive war memorial. A short distance below the village is the early Christian chapel of Ayios Stratiyas. Overlooking the village from its mountainous perch is the impressive Monastery of Panayia Yiatrissa.

After the Orlov Revolt of 1770 failed, the Ottomans wanted to punish the Klephts for participating. In the 1780 siege of Kastania, the Ottoman commander Ali Bey besieged the two Maniot pyrgoi (fighting towers) which belonged to the Venetsanakis clan.^[3] With them was Theodoros Kolokotronis and his pregnant wife.

Ali Bey laid siege to the pyrgoi. After holding out for three days the defenders burst out of the doors and charged the Ottomans. Only a few cut through the Ottoman lines; amongst them was Kolokotronis' wife, disguised as a man. She would soon give birth to Konstantinos Kolokotronis, an important figure of the Greek War of Independence which began in 1821.^{[citation needed]}