Corno Grande (2,912m) is the highest peak in the Apennines — the backbone of Italy. Below the summit, the Calderone glacier is the southernmost in Europe (barely surviving — climate change is reducing it yearly, it may be gone within decades). The Gran Sasso massif defines Abruzzo: the mountain is visible from Rome on clear days (120km), from the Adriatic coast (60km), and from every town in the province of L'Aquila. Campo Imperatore sits on its southern flank. Santo Stefano and Rocca Calascio are in its shadow. The Gran Sasso is not a mountain you visit — it's a mountain that organizes everything around it.
Hike Corno Grande (2,912m): Via Normale from Campo Imperatore — 4-5h round trip, last section requires scrambling (not technical but exposed). The view from the summit: both coasts on clear days — Adriatic east, Tyrrhenian west. The Calderone glacier: Between the two peaks of Corno Grande — the southernmost glacier in Europe. Accessible only with crampons+guide (July-September). See it before it disappears. Via ferrata: Several equipped routes on the north face — Brizio, Danesi, Ventricini. For experienced via ferrata climbers. Serious exposure.
Winter: Campo Imperatore ski + backcountry skiing on the plateau. Ice climbing on the north face (Paretone — 600m wall, serious mountaineering). The LNGS underground laboratory: Under 1,400m of rock inside the Gran Sasso tunnel, INFN operates the world's largest underground physics laboratory — dark matter experiments, neutrino detection. Not normally visitable but open days exist.
Cable car from Fonte Cerreto (1,120m) to 2,130m — operating summer and winter. From 2,130m: hiking trails in every direction. From Rome: A24 highway, exit Assergi (1.5h) → Fonte Cerreto cable car. Refuges: Rifugio Duca degli Abruzzi (2,388m — overnight for summit attempts). Rifugio Franchetti (2,433m — north side, for via ferrata). Guide required for glacier and via ferrata. CAI L'Aquila section for guided hikes. Abruzzo →