In the Valtellina, between the N of the Lago di Como and Sondrio.
This is one of the most amazing climbing valleys in the world. It reminds one of Yosemite valley, looking at the white and compact granite faces and mountains.
Short routes with easy access and complex routes of up to 20 pitches with a 2 hour hike access can be found here.
Climbing is mostly a combination of trad and bolted slabs, most of the routes clearly require trad gear and experience. Several routes exhibit quite some run outs. However, there are also some well protectable classics which can be identified in one of the many climbing guide books available for this place.