function strip_param_from_url( $url, $param ) {
$base_url = strtok($url, '?'); // Get the base url
$parsed_url = parse_url($url); // Parse it
$query = $parsed_url['query']; // Get the query string
parse_str( $query, $parameters ); // Convert Parameters into array
unset( $parameters[$param] ); // Delete the one you want
$new_query = http_build_query($parameters); // Rebuilt query string
return $base_url.'?'.$new_query; // Finally url is ready
}
// Usage
echo strip_param_from_url( 'http://url.com/search/?location=london&page_number=1',
'location' )