EDIT
Since, as you mentioned it in comments, it can have several values, maybe we could retrieve the city list and set corresponding rewrite rules like so?
assuming $city_list is an array of cities
foreach ($city_list as $city) {
add_rewrite_rule('/^'. $city .'/destination/'. $city .'$/','index.php?p=idofyourhomepage','top');
}
How about trying some rewrite rules.
add_rewrite_rule('/^london/destination/london$/','index.php?p=idofyourhomepage','top');
Or
add_rewrite_rule('/^london/destination/london$/','index.php?pagename=nameofyourhomepage','top');
Go validate your permalink settings to refresh the rules.