Crema is the town to know here, a walled little city of about thirty thousand people on the Serio river, a short hop east of Milan's commuter sprawl and quite unlike it. The stop sits just outside, among fields and villages such as Capergnanica and Bagnolo Cremasco, in flat Lombard farmland where the horizon is a line of poplars and the Alps show only on very clear winter days.
Do not expect the Val Trebbia itself, which lies well south, in the Apennines toward Bobbio. This is the lowland end of the ride, where the day's altitude has long since drained away and the road is a matter of straight farm lanes, bridges over irrigation canals and the odd roundabout. Surfaces are generally fine, though heavy farm traffic leaves grooves, and after rain the verges carry mud from the beet and maize harvest. Mornings in autumn bring a fog that sits on the plain like cotton wool.
Crema deserves an hour more than most finish points. Its old centre was fortified by Venice, whose border with Milan ran close by for centuries, and the Venetian walls and bastions still shape the town. Piazza Duomo is a tidy square of brick and white stone, the cathedral mixing Lombard Gothic with later changes. The area is known for tortelli cremaschi, a stuffed pasta with a curious sweet filling of amaretti and raisins that surprises anyone expecting plain cheese, and it is worth ordering once for the story alone.
Fuel is no problem in Crema, and the smaller villages around have pumps too, though self-service machines are common outside daytime hours, so carry a note or a card that works with them. Parking in the centre is limited-access in places, so leave the bike on the outer streets if you want to walk the old town. After the Apennine curves, the flatness can feel like a stiff drink after a long meal, but it is a gentle way to let the day settle.