diff --git a/php/edit_place.inc.php b/php/edit_place.inc.php
index 7417921..3b762b1 100644
--- a/php/edit_place.inc.php
+++ b/php/edit_place.inc.php
@@ -110,7 +110,7 @@
 ?>
 
          <label for="timezone_id"><?php echo translate("timezone") ?></label>
-         <?php echo create_timezone_pulldown("timezone_id", $place->get("timezone"), $user); ?>
+         <?php echo TimeZone::createPulldown("timezone_id", $place->get("timezone"), $user); ?>
 <?php
     }
 ?>
diff --git a/php/photo.inc.php b/php/photo.inc.php
index a8a6365..cc2140a 100644
--- a/php/photo.inc.php
+++ b/php/photo.inc.php
@@ -1124,16 +1124,16 @@ public function getEditArray(user $user = null) {
 
     function get_time($timezone=null, $date_format=DATE_FORMAT, $time_format=TIME_FORMAT) { 
         if(minimum_version("5.1.0")) {
-            if(valid_tz($timezone)) {
+            if(TimeZone::validate($timezone)) {
                 $place_tz=new TimeZone($timezone);
             } else { 
                 $this->lookup_location();
                 $loc=$this->location;
-                if($loc && valid_tz($loc->get("timezone"))) {
+                if($loc && TimeZone::validate($loc->get("timezone"))) {
                     $place_tz=new TimeZone($loc->get("timezone"));
                 } 
             }
-            if(valid_tz(CAMERA_TZ)) {
+            if(TimeZone::validate(CAMERA_TZ)) {
                 $camera_tz=new TimeZone(CAMERA_TZ);
             }    
                 
@@ -1174,7 +1174,7 @@ function get_time($timezone=null, $date_format=DATE_FORMAT, $time_format=TIME_FO
 
     function get_time_details() {
         $tz=null;
-        if(valid_tz(CAMERA_TZ)) {
+        if(TimeZone::validate(CAMERA_TZ)) {
             $tz=CAMERA_TZ;
         }
         
@@ -1612,7 +1612,7 @@ public static function removePhotosWithNoValidTZ(array $photos) {
             $loc=$photo->location;
             if(get_class($loc)=="place") {
                 $tz=$loc->get("timezone");
-                if(valid_tz($tz)) {
+                if(TimeZone::validate($tz)) {
                     $gphotos[]=$photo;
                 }
             }
@@ -1778,7 +1778,7 @@ function create_rating_graph($user) {
  * Function to rotate an image
  */
 function goodrotate($src_img, $degrees = 90) {
-    // angles = 0°
+    // angles = 0deg
     $degrees %= 360;
     if($degrees == 0) {
         $dst_img = $src_image;
diff --git a/php/place.inc.php b/php/place.inc.php
index dc472ac..b90a03a 100644
--- a/php/place.inc.php
+++ b/php/place.inc.php
@@ -104,7 +104,7 @@ function getChildren($user=null,$order=null) {
     function tzid_to_timezone() {
         $tzkey=$this->get("timezone_id");
         if($tzkey>0) {
-            $tzarray=get_tz_select_array();
+            $tzarray=TimeZone::getSelectArray();
             $tz=$tzarray[$tzkey];
             $this->set("timezone", $tz);
         } else {
@@ -472,7 +472,7 @@ function guess_tz() {
         $lon=$this->get("lon");
         $timezone=$this->get("timezone");
         if((!$timezone && $lat && $lon) && minimum_version("5.1.0")) {
-            $tz=guess_tz($lat, $lon);
+            $tz=TimeZone::guess($lat, $lon);
             if($tz) {
                 $html="<span class='actionlink'>" .
                     "<a href=place.php?_action=update&place_id=" .
diff --git a/php/timezone.inc.php b/php/timezone.inc.php
index 5678ac6..244f791 100644
--- a/php/timezone.inc.php
+++ b/php/timezone.inc.php
@@ -42,12 +42,73 @@ function get_xml($search) {
             $xml->appendChild($rootnode);
             return $xml->saveXML();
         }   
+        public static function getSelectArray() {
+            $zones=self::listIdentifiers();
+            array_unshift($zones, "");
+            return $zones;
+        }
+        
+        public static function getKey($tz) {
+            return array_search($tz,self::getSelectArray());
+        }
+
+        public static function createPulldown($name, $value=null, $user=null) {
+            $id=preg_replace("/^_+/", "", $name);
+            if($value) {
+                $text=$value;
+            } else {
+                $text="";
+            }
+
+            if(AUTOCOMPLETE && JAVASCRIPT) {
+                $html="<input type=hidden id='" . $id . "' name='" . $name. "'" .
+                    " value='" . $value . "'>";
+                $html.="<input type=text id='_" . $id . "' name='_" . $name. "'" .
+                    " value='" . $text . "' class='autocomplete'>";
+            } else {
+                $html=create_pulldown("timezone_id", self::getKey($value), self::getSelectArray());
+            }
+            return $html;
+        }
+
+
+        public static function validate($tz) {
+            // Checks if $tz contains a valid timezone string
+            $tzones=DateTimeZone::listIdentifiers();
+            return array_search($tz, $tzones);
+        }
+
+        public static function guess($lat, $lon) {
+            if(minimum_version("5.1.2") && class_exists("XMLReader")) {
+                $xml=new XMLReader();
+                @$xml->open("http://ws.geonames.org/timezone?lat=" . 
+                    $lat . "&lng=" . $lon) or $failed=true;
+                
+                if (!$failed) {
+                    while($xml->read() && !$tz) {
+                        if($xml->name=="timezoneId") {
+                            $xml->read();
+                            $tz=$xml->value;
+                        }
+                    }
+                    return $tz;
+                } else {
+                    $error=error_get_last();
+                    log::msg("Could not connect to Geonames site: " . 
+                        $error["message"], log::ERROR, log::GENERAL);
+                    return null;
+                }
+            } else {
+                return null;
+            }
+
+        }    
     }
 
     class Time extends DateTime {
         function __construct($datetime, $tz=null) {
             try {
-                if(valid_tz($tz->getName())) {
+                if(TimeZone::validate($tz->getName())) {
                     parent::__construct($datetime,$tz);
                 } else {
                     parent::__construct($datetime);
@@ -59,64 +120,6 @@ function __construct($datetime, $tz=null) {
         }
     }
 
-function get_tz_select_array() {
-    $zones=DateTimeZone::listIdentifiers();
-    array_unshift($zones, "");
-    return $zones;
-}
-
-function get_tz_key($tz) {
-    return array_search($tz,get_tz_select_array());
-}
-
-function guess_tz($lat, $lon) {
-    if(minimum_version("5.1.2") && class_exists("XMLReader")) {
-        $xml=new XMLReader();
-        @$xml->open("http://ws.geonames.org/timezone?lat=" . 
-            $lat . "&lng=" . $lon) or $failed=true;
-        
-        if (!$failed) {
-            while($xml->read() && !$tz) {
-                if($xml->name=="timezoneId") {
-                    $xml->read();
-                    $tz=$xml->value;
-                }
-            }
-            return $tz;
-        } else {
-            $error=error_get_last();
-            log::msg("Could not connect to Geonames site: " . 
-                $error["message"], log::ERROR, log::GENERAL);
-            return null;
-        }
-    } else {
-        return null;
-    }
-}
-function create_timezone_pulldown($name, $value=null, $user=null) {
-    $id=preg_replace("/^_+/", "", $name);
-    if($value) {
-        $text=$value;
-    } else {
-        $text="";
-    }
-
-    if(AUTOCOMPLETE && JAVASCRIPT) {
-        $html="<input type=hidden id='" . $id . "' name='" . $name. "'" .
-            " value='" . $value . "'>";
-        $html.="<input type=text id='_" . $id . "' name='_" . $name. "'" .
-            " value='" . $text . "' class='autocomplete'>";
-    } else {
-        $html=create_pulldown("timezone_id", get_tz_key($value), get_tz_select_array());
-    }
-    return $html;
-}
 
 
-function valid_tz($tz) {
-    // Checks if $tz contains a valid timezone string
-    $tzones=DateTimeZone::listIdentifiers();
-    return array_search($tz, $tzones);
-}
-    
 ?>