Northern California is a traveller's paradise and truly has it all. It's the perfect road trip destination because it has such a diversity of things to see, do, eat and sip.
As you start planning out your road trip itinerary, you'll be making concessions and be forced to cut things out because you'll be balancing the time required to drive to get around and also what makes sense to fit in.
The tour you want to look at is California Dreamin': Northern California By Design and this is one of their newest tours that incorporates what's called Choice Touring.
When it comes to weather and the most favourable conditions for a road trip, I'd pick the shoulder season so that's April to May and September to October with spring having a slight edge
Your Northern California road trip adventures starts off with a bang. If you've never been to San Francisco, you'll want to cram in as much as you can in the city.