The project was characterized by:
a) Attention to the choice of building methods to ensure perfect operation and long structural life, and minimize the duration of the building operations;
b) Safety in the tunnel both in ordinary working conditions and in emergencies, with particular attention to escape routes for users (construction of escape routes under the road surface and building of a road and pedestrian bypass) and tunnel air quality (aeration, and extraction and smoke treatment system in the false ceiling);
c) Detailed survey of the expected repercussions of the new infrastructure on the mouth areas;
d) Architectural study of the same areas so the tunnel may be correctly integrated into the urban surroundings;
e) Optimization of the gradient to avoid interference with the metro and underground railway lines (existing and foreseen), and to avoid damaging the foundations of the buildings above.