[citation needed] According to the original project, it will start at the intersection of the avenues Brazil with Vicuña Mackenna in Renca, from where it will start to the south, following the route of the last street it will cross the Mapocho river at the height of the Resbalón bridge in Cerro Navia, and from there it will continue by Rolando Petersen to the south, until its intersection with Mapocho Avenue; here it will go towards the east following this same route, it will cross the communes of Cerro Navia and Quinta Normal, connecting perpendicularly lines 2 and 3 in Puente Cal y Canto, to continue under the park corridor that borders the Mapocho (Forestal and Balmaceda); in this route it will combine with lines 5 and 1 at Baquedano.

After passing through the Balmaceda park following Andrés Bello, it will continue to connect with the Line 1 at Pedro de Valdivia, then head through the Southern border of Vitacura until Alonso de Córdova, where it will connect with Presidente Kennedy to finish its route in the junction of Presidente Kennedy with Estoril in Las Condes and Vitacura.

Chilean transport experts have proposed that the line be modified to serve the city's international airport by running through San Daniel, Rio Itata and Armando Cortínez Oriente avenues in Pudahuel, passing through the Enea business park and with 22 stations, adding four and removing the three most western of the project.

On December 22, 2017 the newspaper El Mercurio published a report that indicated that the route of the line was modified, so it will not circulate along Andrés Bello Avenue, but will go parallel to Line 1 through Providencia Avenue, eliminating a planned transfer in Salvador and transferring it to Pedro de Valdivia, to then continue with its original layout in Isidora Goyenechea (where it will combine with Line 6 in a station with the same name), and a section of the route in the sector of Kennedy Avenue will be diverted by Cerro Colorado.

[5] In addition to the logical benefits that it will bring in terms of transfer times, Line 7 stands out for its contribution to the socio-economic and geographical integration of the city, since it connects the most neglected and deteriorated parts in terms of urban investment, infrastructure and connection, as it is the northwest of Santiago, with the center and northeast of the city, where the commerce and the jobs prevail.