echo date_default_timezone_get(); //UTC
//Read more at https://www.php.net/manual/en/function.date-default-timezone-get.php
//To Get the list of timezones available in php
//use the static function listIdentifiers() on DateTimeZone class
$list = DateTimeZone::listIdentifiers();
print_r($list)
$tzlist = DateTimeZone::listIdentifiers(DateTimeZone::ALL);