The departure of the northwesterly runway (RWY 31), as Tightslot said, does indeed have a high density of hills that we'd rather avoid. So, the published departure takes us straight ahead for a couple of miles followed by a 180 degree right turn back out over the sea. Then, once past the coast, a 180 degree turn left again before a 40 degree (ish) turn to the right to continue on route.
Quite often, we can get high enough quick enough to enable us to have to make only half of the initial right turn before continuing directly north overland. If this is the case, we'll ask ATC for a direct route north.
However, because the Spanish Controllers aren't happy with their E120,000 a year, they are on a Go-Slow, so are more often than not making us fly the whole convoluted procedure, even though we are able to fly direct over land.
Hope this helps!