The referendum asked if voters approved of the new terms of a bailout offered by the nation's creditors. Prime Minister Alexis Tsipras had referred the matter to the public for a vote and asked for a 'No' vote, in hopes of improving his bargaining position. For more background and a roundup of reactions, see here and here.
From an elections perspective, not only was this a poke in the eye for European leaders, it was also another failure for polls, which had been predicting a close result in the days leading up to the vote.
The landslide was far from uniform, however. The strongest opposition can be seen around the edges (but not at the center) of urban areas, and on the island of Crete.
More than a dozen municipalities approved the referendum, including Filothei-Psychiko (Φιλοθέη-Ψυχικό), which voted 71.6 percent "Yes" on the referendum. It's probably no coincidence that this municipality contains some of the wealthiest neighborhoods in the country.
