Convert coordinates to City name?

import Foundation
import CoreLocation
import PlaygroundSupport
PlaygroundPage.current.needsIndefiniteExecution = true

let location = CLLocation(latitude: 37.3321, longitude: -122.0318)
CLGeocoder().reverseGeocodeLocation(location) { placemarks, error in
    
    guard let placemark = placemarks?.first else {
        let errorString = error?.localizedDescription ?? "Unexpected Error"
        print("Unable to reverse geocode the given location. Error: \(errorString)")
        return
    }
    
    let reversedGeoLocation = ReversedGeoLocation(with: placemark)
    print(reversedGeoLocation.formattedAddress)
    // Apple Inc.,
    // 1 Infinite Loop,
    // Cupertino, CA 95014
    // United States
}

struct ReversedGeoLocation {
    let name: String            // eg. Apple Inc.
    let streetNumber: String    // eg. 1
    let streetName: String      // eg. Infinite Loop
    let city: String            // eg. Cupertino
    let state: String           // eg. CA
    let zipCode: String         // eg. 95014
    let country: String         // eg. United States
    let isoCountryCode: String  // eg. US
    
    var formattedAddress: String {
        return """
        \(name),
        \(streetNumber) \(streetName),
        \(city), \(state) \(zipCode)
        \(country)
        """
    }
    
    // Handle optionals as needed
    init(with placemark: CLPlacemark) {
        self.name           = placemark.name ?? ""
        self.streetName     = placemark.thoroughfare ?? ""
        self.streetNumber   = placemark.subThoroughfare ?? ""
        self.city           = placemark.locality ?? ""
        self.state          = placemark.administrativeArea ?? ""
        self.zipCode        = placemark.postalCode ?? ""
        self.country        = placemark.country ?? ""
        self.isoCountryCode = placemark.isoCountryCode ?? ""
    }
}

---

Old/Deprecated answer:

Thanks to @Kampai's answer, here's a Swift 3 compatible and safer way (no forcing !):

let geoCoder = CLGeocoder()
let location = CLLocation(latitude: touchCoordinate.latitude, longitude: touchCoordinate.longitude)

geoCoder.reverseGeocodeLocation(location, completionHandler: { placemarks, error in
    guard let addressDict = placemarks?[0].addressDictionary else {
        return
    }
    
    // Print each key-value pair in a new row
    addressDict.forEach { print($0) }
    
    // Print fully formatted address
    if let formattedAddress = addressDict["FormattedAddressLines"] as? [String] {
        print(formattedAddress.joined(separator: ", "))
    }
    
    // Access each element manually
    if let locationName = addressDict["Name"] as? String {
        print(locationName)
    }
    if let street = addressDict["Thoroughfare"] as? String {
        print(street)
    }
    if let city = addressDict["City"] as? String {
        print(city)
    }
    if let zip = addressDict["ZIP"] as? String {
        print(zip)
    }
    if let country = addressDict["Country"] as? String {
        print(country)
    }
})

---

Don't forget NSLocationWhenInUseUsageDescription and NSLocationAlwaysUsageDescription keys

For Swift 3: and Swift 4

First you need to set allowance to receive User's GPS in the info.plist.

Set: NSLocationWhenInUseUsageDescription with a random String. And/or: NSLocationAlwaysUsageDescription with a random String.

Then I have set up a class to get the desired data like zip, town, country...:

import Foundation
import MapKit

typealias JSONDictionary = [String:Any]

class LocationServices {

    let shared = LocationServices()
    let locManager = CLLocationManager()
    var currentLocation: CLLocation!

    let authStatus = CLLocationManager.authorizationStatus()
    let inUse = CLAuthorizationStatus.authorizedWhenInUse
    let always = CLAuthorizationStatus.authorizedAlways

    func getAdress(completion: @escaping (_ address: JSONDictionary?, _ error: Error?) -> ()) {

        self.locManager.requestWhenInUseAuthorization()

        if self.authStatus == inUse || self.authStatus == always {

            self.currentLocation = locManager.location

            let geoCoder = CLGeocoder()

            geoCoder.reverseGeocodeLocation(self.currentLocation) { placemarks, error in

                if let e = error {

                    completion(nil, e)

                } else {

                    let placeArray = placemarks as? [CLPlacemark]

                    var placeMark: CLPlacemark!

                    placeMark = placeArray?[0]

                    guard let address = placeMark.addressDictionary as? JSONDictionary else {
                        return
                    }

                    completion(address, nil)

                }

            }

        }

    }

}

Called by:

import UIKit

class ViewController: UIViewController {

    override func viewDidLoad() {
        super.viewDidLoad()
        LocationServices.shared.getAdress { address, error in

            if let a = address, let city = a["City"] as? String {
               //
            }

        }

    }

}

Done

---

SWIFT 4.2 : EDIT

---

MapKit framework does provide a way to get address details from coordinates.

You need to use reverse geocoding of map kit. CLGeocoder class is used to get the location from address and address from the location (coordinates). The method reverseGeocodeLocation will returns the address details from coordinates.

This method accepts CLLocation as a parameter and returns CLPlacemark, which contains address dictionary.

So now above method will be updated as:

@objc func didLongPressMap(sender: UILongPressGestureRecognizer) {

    if sender.state == UIGestureRecognizer.State.began {
        let touchPoint = sender.location(in: mapView)
        let touchCoordinate = mapView.convert(touchPoint, toCoordinateFrom: self.mapView)
        let annotation = MKPointAnnotation()
        annotation.coordinate = touchCoordinate
        annotation.title = "Your position"
        mapView.addAnnotation(annotation) //drops the pin
        print("lat:  \(touchCoordinate.latitude)")
        let num = touchCoordinate.latitude as NSNumber
        let formatter = NumberFormatter()
        formatter.maximumFractionDigits = 4
        formatter.minimumFractionDigits = 4
        _ = formatter.string(from: num)
        print("long: \(touchCoordinate.longitude)")
        let num1 = touchCoordinate.longitude as NSNumber
        let formatter1 = NumberFormatter()
        formatter1.maximumFractionDigits = 4
        formatter1.minimumFractionDigits = 4
        _ = formatter1.string(from: num1)
        self.adressLoLa.text = "\(num),\(num1)"

        // Add below code to get address for touch coordinates.
        let geoCoder = CLGeocoder()
        let location = CLLocation(latitude: touchCoordinate.latitude, longitude: touchCoordinate.longitude)
        geoCoder.reverseGeocodeLocation(location, completionHandler:
            {
                placemarks, error -> Void in

                // Place details
                guard let placeMark = placemarks?.first else { return }

                // Location name
                if let locationName = placeMark.location {
                    print(locationName)
                }
                // Street address
                if let street = placeMark.thoroughfare {
                    print(street)
                }
                // City
                if let city = placeMark.subAdministrativeArea {
                    print(city)
                }
                // Zip code
                if let zip = placeMark.isoCountryCode {
                    print(zip)
                }
                // Country
                if let country = placeMark.country {
                    print(country)
                }
        })
    }
}