Centuries: 4th century BC - 3rd century BC - 2nd century BC
Decades: 270s BC 260s BC 250s BC 240s BC 230s BC - 220s BC - 210s BC 200s BC 190s BC 180s BC 170s BC
Years: 225 BC 224 BC 223 BC 222 BC 221 BC - 220 BC - 219 BC 218 BC 217 BC 216 BC 215 BC
- October/November - Pharaoh Ptolemy IV of Egypt marries his sister, who rises to the throne as Arsinoe III of Egypt.
- Eratosthenes measures the size of the Earth.
- On the island Crete, the Gortynians occupy Matala.
- The Romans begin work on the Via Flaminia, a road leading north out of the city.