You always could fly into Gib, it just depended on how you got there. Did it myself years ago in a 172. South coast, across the channel, Brest peninsular and west coast of france to Biarritz. Then across Spain to Seville. Had to go down to Tangiers before coming back to Gib but not now.
It's a good trip and well worth it. I would recomend checking the weather carefully (very wind dependant) and go up to the tower at Gib to get the full briefing. Enjoy!