Query gaat mis :S

Mijn query is als volgd:
<?php
$result = mysql_query("SELECT titel,door FROM forum_topics ORDER BY datum DESC WHERE cat= '1'")or die (mysql_error());
?>
dan krijg ik de fout:
You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'WHERE cat= '1'' at line 1