If your trip to Madrid is all locked in but your travel itinerary is a bit on the empty side, we can give you a helping hand.Think of Madrid and then say the first thing that comes to mind. Bet you said "Plaza Mayor," right? Being such a well-known landmark, you just can't miss it. Toss your suitcases into the back seat and check it off your bucket list.You'll need to jump out of bed early if you're planning to see all the great sights that this place has to offer. Thyssen-Bornemisza National Museum and Almudena Cathedral are no-brainers. Royal Palace of Madrid and El Rastro shouldn't be missed either.Plan a stop at Gran Via Street. It's one attraction you'll usually find on most visitors' must-do lists. Puerta del Sol and Madrid Rio are also close by and worth a pit stop.