diff --git a/motorradig/app/Http/Controllers/TourController.php b/motorradig/app/Http/Controllers/TourController.php
index f7450a0..782c038 100644
--- a/motorradig/app/Http/Controllers/TourController.php
+++ b/motorradig/app/Http/Controllers/TourController.php
@@ -3,6 +3,7 @@
 namespace App\Http\Controllers;
 
 use App\Tour;
+use App\Booking;
 use Illuminate\Http\Request;
 use Illuminate\Http\File;
 use Illuminate\Support\Facades\Storage;
@@ -177,4 +178,16 @@ class TourController extends Controller
         //
     }
 
+    public function join($tour_id) {
+        $user=Auth::user();
+        Tour::join($tour_id,$user->id);
+        return redirect('/tour');
+    }
+
+    public function cancelBooking($tour_id) {
+        $user=Auth::user();
+        Booking::where('tour_id', $tour_id)->where('user_id', $user->id)->delete();
+        return redirect('/tour');
+    }
+
 }
diff --git a/motorradig/app/Tour.php b/motorradig/app/Tour.php
index f33c539..0b200fa 100644
--- a/motorradig/app/Tour.php
+++ b/motorradig/app/Tour.php
@@ -3,6 +3,7 @@
 namespace App;
 
 use Illuminate\Database\Eloquent\Model;
+use Carbon\Carbon;
 
 class Tour extends Model
 {
@@ -25,14 +26,22 @@ class Tour extends Model
     }
 
     public static function join($tour_id,$user_id) {
+        error_log("Tour::join, tour_id=".$tour_id.", user_id=".$user_id);
+        /*
         Booking::firstOrCreate(
             ['tour_id',$tour_id],
             ['user_id',$user_id],
-            ['updated_at', \Carbon::now()]
+            ['updated_at', Carbon::now()]
         );
+        */
+        $booking = Booking::firstOrCreate(
+            ['tour_id' => $tour_id, 'user_id' => $user_id],
+            ['tour_id' => $tour_id, 'user_id' => $user_id, 'created_at' => Carbon::now(), 'updated_at' => Carbon::now() ]
+        );
+        error_log($booking);
     }
 
-    public static function leave($tour_id, $user_id) {
+    public static function cancel($tour_id, $user_id) {
         Booking::where('tour_id',$tour_id)->where('user_id',$user_id)->delete();
     }
 }
diff --git a/motorradig/app/User.php b/motorradig/app/User.php
index e79dab7..148f121 100644
--- a/motorradig/app/User.php
+++ b/motorradig/app/User.php
@@ -36,4 +36,12 @@ class User extends Authenticatable
     protected $casts = [
         'email_verified_at' => 'datetime',
     ];
+
+    public static function has_tour($tour_id, $user_id) {
+        $tour=Tour::find($tour_id);
+        $user=User::first($user_id);
+        $booking=Booking::where('tour_id', $tour_id)->where('user_id', $user_id);
+        if ($booking) return true;
+        return false;
+    }
 }
diff --git a/motorradig/database/seeds/BookingSeeder.php b/motorradig/database/seeds/BookingSeeder.php
index 94532b7..14992de 100644
--- a/motorradig/database/seeds/BookingSeeder.php
+++ b/motorradig/database/seeds/BookingSeeder.php
@@ -13,38 +13,58 @@ class BookingSeeder extends Seeder
     {
         DB::table('bookings')->insert([
             'user_id' => 1,
-            'tour_id' => 1
+            'tour_id' => 1,
+            'created_at' => Carbon::now(),
+            'updated_at' => Carbon::now(),
         ]);
         DB::table('bookings')->insert([
             'user_id' => 2,
-            'tour_id' => 1
+            'tour_id' => 1,
+            'created_at' => Carbon::now(),
+            'updated_at' => Carbon::now(),
         ]);
         DB::table('bookings')->insert([
             'user_id' => 3,
-            'tour_id' => 1
+            'tour_id' => 1,
+            'created_at' => Carbon::now(),
+            'updated_at' => Carbon::now(),
         ]);
         DB::table('bookings')->insert([
             'user_id' => 4,
-            'tour_id' => 2
-        ]);DB::table('bookings')->insert([
+            'tour_id' => 2,
+            'created_at' => Carbon::now(),
+            'updated_at' => Carbon::now(),
+        ]);
+
+        DB::table('bookings')->insert([
         'user_id' => 5,
-        'tour_id' => 2
+        'tour_id' => 2,
+            'created_at' => Carbon::now(),
+            'updated_at' => Carbon::now(),
     ]);
         DB::table('bookings')->insert([
             'user_id' => 2,
-            'tour_id' => 3
+            'tour_id' => 3,
+            'created_at' => Carbon::now(),
+            'updated_at' => Carbon::now(),
         ]);
         DB::table('bookings')->insert([
             'user_id' => 3,
-            'tour_id' => 3
+            'tour_id' => 3,
+            'created_at' => Carbon::now(),
+            'updated_at' => Carbon::now(),
         ]);
         DB::table('bookings')->insert([
             'user_id' => 4,
-            'tour_id' => 3
+            'tour_id' => 3,
+            'created_at' => Carbon::now(),
+            'updated_at' => Carbon::now(),
         ]);
         DB::table('bookings')->insert([
             'user_id' => 6,
-            'tour_id' => 3
+            'tour_id' => 3,
+            'created_at' => Carbon::now(),
+            'updated_at' => Carbon::now(),
         ]);
     }
 }
diff --git a/motorradig/resources/views/tour/show.blade.php b/motorradig/resources/views/tour/show.blade.php
index 7b04c70..f93b6e4 100644
--- a/motorradig/resources/views/tour/show.blade.php
+++ b/motorradig/resources/views/tour/show.blade.php
@@ -64,10 +64,15 @@
                                 </textarea>
                             </div>
 
-
+                            <!-- TODO: Only if owner or admin -->
                             <a href="/tour/{{$tour->id}}/edit"><div type="submit" class="btn btn-danger col-3 mb-2 float-left mr-2">Bearbeiten</div></a>
                             <a href="/tour" type="submit" class="btn btn-success col-3 mb-2 float-right mr-2">Ok</a>
-                            <a href="#" type="submit" class="btn btn-danger col-3 mb-2 float-right mr-2">Teilnehmen</a>
+
+                            @if(!App\Tour::has_participant($tour->id, Auth::user()->id))
+                                <a href="/tour/{{$tour->id}}/join" type="submit" class="btn btn-danger col-3 mb-2 float-right mr-2">Teilnehmen</a>
+                            @else
+                                <a href="/tour/{{$tour->id}}/cancelBooking" type="submit" class="btn btn-danger col-3 mb-2 float-right mr-2">Absagen</a>
+                            @endif
 
 
                         </form>
diff --git a/motorradig/routes/web.php b/motorradig/routes/web.php
index 7244809..9ff9d6b 100644
--- a/motorradig/routes/web.php
+++ b/motorradig/routes/web.php
@@ -44,6 +44,8 @@ Route::get('/admin/edit_activities', 'AdminController@edit_activities');
 Route::post('/admin/store_activities', 'AdminController@store_activities');
 
 Route::resource('/tour', TourController::class);
+Route::get('/tour/{tour_id}/join', 'TourController@join');
+Route::get('/tour/{tour_id}/cancelBooking', 'TourController@cancelBooking');
 
 Auth::routes();