Dynamic urls and getting data from multiple tables

Hi, I'm very new to laravel and mysql aswell.

I'm trying to create urls like this: /Afrika/Egypte/Cairo/Cairo-International-Airport.

In my web.php i have set a route like this: Route::get('{continent}/{country}/{city}/{airportname}

/airports -> lists all airports /{continent}/{country} -> list of airports in that country /{continent}/{country}/{city} -> list of airports in that city /{continent}/{country}/{city}/{airport} -> shows airport info of that specific airport

I have set up 3 tables. A

• countries table (id, countryName, slug and continent).
• cities table (id, cityName, slug, country_id)
• airports table (id (primary), airportName, slug, city_id (foreign) and country_id (foreign))

In my controller i have this for the single airport:

public function show($continent, $country, $city, $airportname)
{
    $airport = Airport::where('slug', $airportname)->first();
    return view('airports.show', ['airport' => $airport], compact('continent', 'country', 'city', 'airportname'));      
}

This works ok, but when i add an airport to the url that does not match the city or country it will work to. It should be linked to the city_id or something like that. But i dont know how to make that work. Same for list of of airport when the end of the url is a city. I want to show the cityname and not an id in the url, but i only want to list the airports that belongs to that specific city.

My Airport model looks like this:

public function path() { return route('airports.show', this); }

public function city() { return $this->belongsTo(City::class); }

public function country() { return $this->belongsTo(Country::class); }