How To Make A Collection Of Two Models Grouped By Date In Laravel 5.5?

I have two models Tour and Adventure. I want to make a group of both tours and adventures grouped by date. And display it like this:

July 17

Tour 1 Tour 2 Tour 3 Adventure 1 Adventure 2 Adventure 3

July 16

Tour 1 Tour 2 Tour 3 Adventure 1 Adventure 2 Adventure 3

I know how to make the grouping of a single model. It goes like this:

Tour::orderBy('created_at', 'desc')->take(20)->get()->groupBy(function($item)
          {
            return $item->created_at->format('d-M-y');
          });

How can I join the two models and display them into a single date? With the current code day appear in different collections.

EDIT: Including the table migrations.

public function up()
    {
        Schema::create('tours', function (Blueprint $table) {
          $table->increments('id');

          $table->string('name', 125);
          $table->string('slug')->index();
          $table->text('description')->nullable();
          $table->string('duration')->nullable();
          $table->string('url')->nullable();

          $table->boolean('ended')->default(false)->index();

          $table->timestamps();
        });
        DB::statement('ALTER TABLE tours ADD FULLTEXT search(name)');
    }

The migration for the adventure model is the same as the tour. The two models does not share a relationship between them.

I think your looking for the merge() method for merging two collection laravel.com/docs/5.8/collections#method-merge

        //Get all Tours
        $tours= Tour::orderBy('created_at', 'desc')->get();

        //Get all adventures
        $adventures= Adventure::orderBy('created_at', 'desc')->get();

        //Merge both collection into 1 single collection and group according the date
        $dates= $tours->merge($adventures)->groupBy(function($item) {
            return $item->created_at->format('d-M-y');
        });

        return view('someView', compact('dates'));

And then you can loop within the date

        @foreach($dates as $date => $activity)
            <h2>{{$date}}</h2>
            <li>
                {{$activity}}
            </li>
        @endforeach