I was taking pictures of this fortress called forte do guincho, near cascais, lisbon. i didn't notice the object untill i saw the picture. i took one in the same place less than a minute before and another a minute after and the object does not appear in any of these (before and after). when i saw it (in the picture) i thought of a cigar shape ufo. i only can describe it as something clear cigar shape, very high in the sky, grey. i would like to know what can it be...A plane, an ufo? what do you think about it? thank you.