It is said to be the world's first weather station, to date back more than 2,000 years, and to have been used by merchants to tell the time - even in darkness.
Links:
[1] http://admin.indiaenvironmentportal.org.in/news/ancient-greeces-restored-tower-winds-keeps-its-secrets
[2] http://admin.indiaenvironmentportal.org.in/category/newspaper/planet-ark-australia
[3] http://admin.indiaenvironmentportal.org.in/category/thesaurus/atmosphere-and-ozone-layer
[4] http://admin.indiaenvironmentportal.org.in/category/thesaurus/weather-predictions
[5] http://admin.indiaenvironmentportal.org.in/category/thesaurus/atmosphere
[6] http://admin.indiaenvironmentportal.org.in/category/thesaurus/greece
[7] http://admin.indiaenvironmentportal.org.in/category/thesaurus/europe