Which Italian national park contains the highest peak in the Apennines?

The Italian national park containing the highest peak in the Apennines is Gran Sasso and Monti della Laga National Park.

The park is centered partly on the Gran Sasso massif, whose summit, Corno Grande, reaches 2,912 metres. That makes Corno Grande the highest point in the Apennine Mountains and the highest peak on the Italian mainland outside the Alps. The massif lies in central Italy, primarily in Abruzzo.

Gran Sasso and Monti della Laga National Park was established in 1991 and protects a varied landscape of limestone peaks, high plateaus, forests, valleys, and traditional mountain villages. Beneath Corno Grande is the Calderone Glacier, one of Europe's southernmost glaciers, although it has substantially shrunk over time.

The park's name can cause confusion because Gran Sasso is both a mountain massif and part of the park's title. The highest peak is not called “Gran Sasso” itself in the strict sense: it is Corno Grande, within the Gran Sasso massif. The nearby Monti della Laga form a separate mountain group.