You are on road LE-321. On your left (coming from the South) near the end of the Hoces de Vegacervera cannon you´ll find a long corridor. You can leave your car in Lugueros or park it on the side of the roud. There are room enough for a big car.
If you don´t know how to go there have a look at the Main Page.
After park the car you´ll start inmediatelly to go up.
Below you have different views of the corridor.
This is maybe the more direct route of all, but it´s the hardest too.
The main difficulties are the stones on the corridor an the high inclination. The ascension is ethernal! really long. Most of the height you need to climb you´ll get here.
Finally you´ll get a col where you can see for the first time your target: the Fontún´s summit. It´s easy. Just go there. It´s very intuitive but you can use your imagination.
You´ll get another col and then you´ll turn right to get the top of the mountain.
A pole will be specially usefull along the corridor. In fact you´ll use it to the top. If you go down through the same corridor it will be crucial.
In winter crampons and ice-axe are essential. I´d take a rope too.
I haven´t done this route on winter, but I believe it must be dangerous, so don´t choose this ascension if you don´t have good equipment, experience and good climbing skills