Free walking tour in Madrid: how it works and how much it costs

What is a free walking tour really, why isn't it completely free, how much do you usually contribute at the end, and how to choose a worthwhile one in Madrid?.
Guided tour of Madrid: what a good experience should include

The twenty signs that distinguish a good guided tour of Madrid, from the meeting point to transparency about the price.
How much does a private tour in Madrid cost and what should it include?

What determines the price of a private tour in Madrid and what should it always include to make the experience worthwhile?.
Private tour of Madrid: when it's worth hiring an exclusive guide

Advantages of a private tour of Madrid versus a shared tour, when it is worth hiring one, what it should include and what its price depends on.
Literary Quarter: living history among cafes and literature

Discover Madrid's Literary Quarter: what to see, its Golden Age history, the cafes where writers met, and practical tips for exploring it on foot.
Preciados Street: history of Madrid's main shopping street

The history of Preciados Street, from the 15th-century almotacene brothers who gave it its name to becoming one of the busiest pedestrian streets in Europe.