List of Supported Timezones
PHP Manual

Europe

Europe
Europe/Amsterdam Europe/Andorra Europe/Astrakhan Europe/Athens
Europe/Belgrade Europe/Berlin Europe/Bratislava Europe/Brussels
Europe/Bucharest Europe/Budapest Europe/Busingen Europe/Chisinau
Europe/Copenhagen Europe/Dublin Europe/Gibraltar Europe/Guernsey
Europe/Helsinki Europe/Isle_of_Man Europe/Istanbul Europe/Jersey
Europe/Kaliningrad Europe/Kiev Europe/Kirov Europe/Lisbon
Europe/Ljubljana Europe/London Europe/Luxembourg Europe/Madrid
Europe/Malta Europe/Mariehamn Europe/Minsk Europe/Monaco
Europe/Moscow Europe/Oslo Europe/Paris Europe/Podgorica
Europe/Prague Europe/Riga Europe/Rome Europe/Samara
Europe/San_Marino Europe/Sarajevo Europe/Simferopol Europe/Skopje
Europe/Sofia Europe/Stockholm Europe/Tallinn Europe/Tirane
Europe/Ulyanovsk Europe/Uzhgorod Europe/Vaduz Europe/Vatican
Europe/Vienna Europe/Vilnius Europe/Volgograd Europe/Warsaw
Europe/Zagreb Europe/Zaporozhye Europe/Zurich  

List of Supported Timezones
PHP Manual