It is 10.30 pm but a warm breeze blows up Balcarce when we leave the restaurant. A colectivo on diversion rattles the cobbles as we pass the gay lights of Cafe Rivas towards Defensa, Bolivar and Peru.
Our destination tonight is the Bendita milonga at Peru 571 and five of us pick our way along the broken pavements. Our table is reserved only until 10.45 pm so we haste.
From the outside, Peru 571 is just another doorway in another San Telmo street. It gives little away, save that you know it must be a milonga by the five or six smokers who linger on the footway to stub a cigarette with their dance shoes. The staircase rises steeply straight ahead, to turn at the top through double doors to the salon. Whilst the stairs are dark, it takes a few seconds for your eyes to adjust to the room which is darker still. Lighting in Bendita is strategic rather than effective. We pay 40 pesos for entry and turn to our table directly beneath the stage. It bears a large sign, 'Reserva Twist'.
Bendita milonga is all about El Afronte. Eleven musicians meet each Monday and Wednesday night to play tango here. They comprise three violins, cello, acoustic base, piano, four bandoneons and the singer. Their hallmark is a deep, heavy base line, searing melodies, and complex contra-rhythm. The effect is explosive.
We arrive as the DJ concludes her set. For a moment there is total darkness; and the orchestra appears. Their opening song is instantly recognisable as tango, yet the timing laminates to catch and release the beat. Tradition dictates that the audience will sit for the first piece, but as the second song starts, dancers rise and move onto the small pista encompassed by tables. Now the drama of the music is enacted on the floor. Tangueros circle in close embrace, to be brought to that single breath that is tango.
We sit, and we dance. We listen with all of our senses, including the diverse vibrations we feel through the original oak floor. Each pair of dancers enters a private world which they alone own, in which they make the rules and interpret the music. The light tenor voice of the singer lifts with emotion and he wipes away tears. The audience of watchers and dancers erupts at the end of the performance. Lights flash and people call for more. The last Gardel song encapsulates the craggy history of tango - its moments of joy and deep crevasses of sadness. At one moment it is as if we witness Carlos Gardel's last moments of life.
Suffused with sound and dance, we depart into the now cool San Telmo night. A taxi slowly cruises to a halt and our friends depart to Palermo. For us, this is a moment of collection, as we walk and chat, rising through Humberto Primo towards Chacabuco and home.