Isola Minore, known until the twentieth century simply as l'isoletta (‘the little island’), is the smallest of the three islands of Lago Trasimeno in central Italy, and the closest to Passignano sul Trasimeno within whose municipal boundaries it lies. It rises to about 20 metres above the level of the lake (itself 258 m above sea level), and takes the form of a comma with dimensions of about 450 x 260 m and an area of some 5 hectares. It is about 470 m NE of the larger island of Isola Maggiore.