The 1.3km underground line operates as an extension of Line 4 and links Zona Rental with Bello Monte, with a journey time of less than five minutes between the two stations. Around 30,000 passengers per day are forecast to use Bello Monte station.

A further 6.3km section is under construction which will extend the line east to Las Mercedes, Simon Bolivar, Bello Campo, and Hugo Chávez. A further 7.1km extension is also being built which will continue the line east from Hugo Chávez to Montecristo, Boleita, El Marques, and Warairarepano.