Timezone Manipulation - laravel

Question

I'm working on a project (online game) where users have the ability to use a coded 'airport' to travel to different countries & cities. Once they have travelled, the cityid within the database will update for example:
cityid = 1 (England - London)
cityid = 2 (USA - LA)
Therefore if a user travels from England to the USA it will store database side cityid = 2.
Now,
Whilst this is functional, I wish to incorporate timezone changes into it (if at all possible) I have tried:
if ($user->cityid == 3)
{
$timestamp ='1502448414'; //Timestamp which you need to convert
$dt = new \DateTime("#$timestamp");
$destinationTimezone = new \DateTimeZone('Mexico/General'); // To which timezone you need to convert
$dt->setTimeZone($destinationTimezone); // Set timezone
echo 'Mexico: '. $dt->format('H:i a'), "\n"; // Echo your changed datetime
}
As you can see, I have used Mexico as a demo to try and figure out my approach.
However, this only fetches the timestamped time rather than the realtime. Im aware, I could simply add the timestamp into a database table and then run a cron every second to update the table but this seems rather a long winded route.
Now within app.php the standard setting is UTC which runs as a realtime clock by returning: date('H:i:s').
My question is (after a lot of google searching) is there a way to manipulate this to make date() output the new time of (USA) when it has been travelled to?
Apologies that I cannot add anymore coding into this question, I have no real idea of how to approach it other than the one stated above.

Answer 1

Using Carbon
if ($user->cityid == 3) {
$dt = \Carbon\Carbon::now("Your current location timezone");
$dt->setTimeZone('Mexico/General');
echo 'Mexico: '. $dt->format('H:i a'), "\n";
}