Combine the flour, sugar, salt and yeast in a large mixing bowl, then work the olive oil in. Add the warm water steadily until you can form a fairly sticky dough. Add a little more water if it is too stiff, then turn out onto a lightly floured surface and knead for 8-10 minutes until smooth and elastic. Place in a large, clean mixing bowl and cover with clingfilm.
Leave to rise in a warm place (an airing cupboard for example) for 2 hours or until doubled in size.
Grease a large baking tray. Turn the dough out onto a lightly floured surface, knock it back and knead again with a tablespoon of the sliced olives for 3-4 minutes until smooth and elastic. Shape into an oval and place on the baking tray. Cover loosely with an oiled piece of clingfilm and leave to rise again for 30-40 minutes.
Pre-heat the oven to 230°C.
Make slashes in the top of the loaf and stud with the remaining olives. Bake for 30-40 minutes until golden and risen. Remove and allow to cool on a wire rack. Slice and serve.