Interesting historical places in Madrid?

Hello! I am traveling to Spain and I am very happy about the trip. I plan to stay in Madrid and visit all the important sites of the Spanish capital. Madrid is a city with a long history and I am sure I’ll find out many interesting things about it. What are interesting historical places in Madrid? Thanx a lot!

Madrid is a very beautiful city and you should visit it not only because of the historic sites and historical places, but also because it offers many beautiful views and entertainment facilities, too. People in Madrid are very kind and friendly and I’m sure you’ll feel great in Madrid. If you like to go sightseeing, I recommend you to go and see the Arab Wall. It is one of the oldest constructions in Madrid and it was meant for protecting the city from the outer attacks. El Palacio Real is also astonishing. It used to be the residence of many royal families throughout history. Plaza de la Villa is also a square you should see.