I will be in Madrid for NYE with my mates. What fun activities are there to do around the city?
There is so much fun in Madrid! You will find it in every corner or alley of this amazing city. There are so many nice places to eat, enjoy and relax. I can give you so many examples or ideas of nice places in Madrid. However, since you are asking about NYE, I will focus on your question. As Janelle said Plaza Puerta del Sol is a good example of a nice place to spend NYE. I will add probably Plaza Mayor where there are many nice restaurants and shows for the pre NYE party. A nice place that I found back in 2012 is Restaurante Palacio de Cibeles where you find besides the restaurant, a nice place for "tapas" and "sangria" and also "Terraza Cibeles" (if you are more into dancing). This is a nice terrace with an spectacular view to La Gran Via. There is also another bar Pub Alhambra with a great ambience and offers delicious tapas. It is located pretty close to a salsa club (unfortunately I don't recall the name)
As I told you before, you will find so many alternatives in Madrid for an unforgettable NYE. Enjoy it!!!
Mentioned in this answer:
I'm sure you probably already know this, but the Puerta del Sol is like the Times Square of Madrid and where everyone gathers to eat their 12 good luck grapes. There's a place called Sala Clamores that plays great music. I'm sure they must have something going on for New Years.