This solution is a transmission line in an urban area, using compact lines and an underground line, due to the city projects, the environmental restrictions found in the periphery of the city and the need to arrive with a line of 230 kV to the Guayabal substation, located in the center of the Aburra Valley, a densely populated urban area. Methods: The compact line allows the use of a corridor of an existing line at 230 kV in a single circuit. It converts this line into a double circuit and limits the oscillation of cables with compact towers and installs intermediate towers to existing ones. the current easement of the line. It is verified the compliance of the restrictions by electric field, magnetic field, audible noise and radio interference. Although the number of usual structures per km is increased, the reuse of an existing corridor is allowed. The section of access to the Guayabal substation is implemented with 3 km in underground line, which is achieved with the connection to 230 kV in a safe way and without affecting land or requiring the acquisition of servitude since the roads of the urban area; in order to eliminate interference with other service networks, the geo-surveying is performed for the location of existing utility networks up to a depth of 4 meters. The electrical dimensioning of the conducting cable and the channeling with the CYMCAP program is carried out. The ductwork is designed in open trench, given the characteristics of the tracks and the existing infrastructure was not considered necessary to use directed drilling technology, the pipe used in the pipeline construction is HDPE high density polyethylene pipe, which allows flexibility and wide turning radiuses and does not require prefabricated elements for the curves, agility was found in the construction Results: It is possible to implement the connection to 230 kV inside a semiurban and urban corridor by means of the implementation of two systems of transmission of energy to high tension little used in the country and that are of a moderate cost. This particular project is very complete, and has had particularly difficult situations, such as finding the solution of the passage of the Medellín River with underground cable using the bridge of 10, without having to use underground perforations (cost reduction). Currently, in the underground aerial transition it must be descended by a hill to half slope, which has implied the development of methods of stabilization of the terrain by means of piles. At the time the detailed civil designs of the splicing chambers were made and finally and within the project they were changed to a design of prefabricated chambers, facilitating the construction times. Conclusions: urban corridors for power transmission lines are becoming more complex every day, so it is necessary to develop constructive solutions using modern technologies in both equipment and calculation tools.