The directions to get to Ciudad Abierta by bus are,
From Valparaiso:
Public transportation: Buses of the company Sol del Pacifico
From: Valparaiso
Destination: Quintero and / or Ventanas and / or Puchuncavi and / or Maintecillo and / or Horcon
Valparaiso: Take the bus at any Stop at the  Errazuriz Avenue (the street parallel to the coast but stuck to the sea next to the railway line)The bus continues along that avenue, to Avenida de España in Viña del Mar.
In Viña del Mar: Avenida Alvares, Plaza Parroquia, Plaza Sucre and Plaza Vergara. The bus continues to Avenida de la Libertad, and then camino international  to Concón.
The bus after Concon takes a roundabout and road to Quintero.
Important: At this point ask the driver to stop at Punta de Piedra-America as 4 km after the roundabout (about 6 or 7 minutes later) that access to the open city (Ciudad Abierta)
From Valparaiso to the roundabout Concon is approximately 45 to 55 minutes.
Take off the bus, the access is on foot from the gray gate. In 5 minutes walk you are in the Music Hall, the meeting point.