U.K. Government advises travellers to be alert due to demonstrations in Greece

Visitors should expect regular strikes and demonstrations. These are sometimes called at short notice and can cause disruption to public transport in and out of Greece (including air travel and ports). See Safety and Security – Local Travel – major pre-planned strikes for more information, and refer to local media reports for updates. Exercise extreme caution around public demonstrations and protests in major urban centres. Violent incidents have occurred at and in the margins of such protests. Tear gas can be used. You should avoid demonstrations and observe instructions and advice given by local security authorities. read article