The small train had ramps that did not exceed 10 thousandths (14% of the total line), or 15 thousandths (11% of the total line), and only 5% were higher than 15 thousandths. The steepest ramp was the one between Quart station and Llambilles halt, which was less than 19 thousandths. The rest of the route was practically flat.

The branch line to the port was a special point. The maximum gradient was 25 thousandths of a kilometre because its route from the upper part of San Feliu to the pass was only 540 metres. The rail on the tracks to the port was 21 kg per metre, somewhat heavier than on the rest of the line. For this reason, when it was operational, the diesel locomotive was used, which was responsible for making shuttles from San Feliu station to the port.