Flight
Flying into Madrid Barajas airport is the best option to get to the wedding, but if you're traveling traveling around Spain/Europe before or after the wedding Barcelona is a good option as well (the high speed train is 2 hours between Barcelona-Madrid)
Travel Note
Renting a car in Madrid is not necessary. Public transportation is an easy way to around the city center. A shuttle to and from the city center for the ceremony and reception will be provided.
House Or Rental
Airbnb is a great option in Spain! Some areas we would recommend: Justicia, Huertas, Retiro, and La Latina. These areas will have a lot going on and will be nearby to the pick up/drop off point for the shuttle to and from the reception.
Hotel
We will have a block of rooms at the NH Madrid Colon hotel for those who would like to stay in the city center. A shuttle will be provided from this hotel to the ceremony and reception (and back!)