With its curved convex façade and elegant Baroque style, the 18th century Basílica Pontífica de San Miguel is my favourite church in Madrid. The Baroque interior complements the outside and has some beautiful frescoes painted on the walls and dome. In my visit to Madrid in November 2007, this church was covered in scaffolding, undergoing some restoration work.
this church is build upon the rememnants of a roman church and is one of the few examples of the so called Bourbon-baroc. There are 4 religious statues to be seen head of the basilica depicting mercy, though, believe and hope. In the roman days the church was devoted to two children who died for the catholic believe, Justo and Pator, who are also depicted in the statue. There are many fresco's to be seen as well as an organ above the entrance porch. The basilica is governed by the Opus Dei group whose founder, De Balaguer, is also depicted in a hugue scary looking statue in one of the shrines.
One of the few Madrid churches inspired with Italina Baroque style. It is worth a stop along your walk though Madrid.