Starving for some good fish and Spanish food? La Maquina is the right place for you.
La Maquina is a restaurant in the heart of Madrid, really close to the main shopping street (Serrano) and Retiro park.
In terms of location, you can either decide to book a table inside, outside or opt for eating “en la barra” in a classy and very well-furnished restaurant. 
The quality is amazing, maybe one of the best I have tried so far in Madrid; I ate a lot, and I digested everything without any problem. Just to give you an idea, I shared gazpacho, anchovies and sardines as a starter, then I ate in pastry seabass with steamed vegetables and as dessert I had a puff pastry stuffed with a sort of whipped cream.
On top of that, they continuously give you very good bread and welcome you with croquetas!