Here's a travel itinerary for exploring California Wine Country, focusing on the renowned regions of Napa Valley and Sonoma County. This itinerary is designed for a 4-day trip, but it can be adjusted based on your preferences and time available.

Day 1: Arrival and Napa Valley

Morning:

• Arrival: Fly into San Francisco International Airport (SFO) or Sacramento International Airport (SMF) and rent a car.
• Drive to Napa Valley: Approximately a 1.5-hour drive from SFO or a 1-hour drive from SMF.

Afternoon:

• Lunch in Napa: Enjoy a meal at Oxbow Public Market, which offers a variety of gourmet food options.
• Winery Visit: Start with a tour and tasting at Domaine Carneros, known for its sparkling wines and stunning château.

Evening:

• Dinner: Dine at a Michelin-starred restaurant like The French Laundry (advance reservations required) or a more casual option like Bottega in Yountville.
• Stay: Check-in at a charming hotel or B&B, such as the Napa River Inn or Hotel Yountville.

Day 2: Napa Valley Exploration

Morning:

• Hot Air Balloon Ride: Start your day with a sunrise hot air balloon ride over Napa Valley for breathtaking views.
• Breakfast: Enjoy a leisurely breakfast at your hotel or a local café like Model Bakery.

Afternoon:

• Winery Visits:
• Castello di Amorosa: Explore this medieval-style castle and winery, known for its architecture and wines.
• V. Sattui Winery: Have a picnic lunch here with food from their artisan deli.

Evening:

• Dinner: Savor dinner at a local favorite like Farmstead at Long Meadow Ranch in St. Helena.
• Stay: Return to your accommodation in Napa Valley.

Day 3: Sonoma County

• Morning:Drive to Sonoma: A scenic 30-minute drive from Napa Valley to Sonoma County.
• Winery Visit: Start with a tasting at Benziger Family Winery, known for its biodynamic wines.

Afternoon:

• Lunch in Sonoma Plaza: Enjoy a meal at the Girl & the Fig, a popular bistro with a focus on fresh, local ingredients.
• Winery Visit: Head to Chateau St. Jean or Jordan Vineyard & Winery for afternoon tastings.

Evening:

• Dinner: Try LaSalette Restaurant in Sonoma for delicious Portuguese cuisine.
• Stay: Check into a cozy inn or resort, such as the Fairmont Sonoma Mission Inn & Spa or MacArthur Place.

Day 4: More of Sonoma and Departure

Morning:

• Winery Visit: Visit Kendall-Jackson Wine Estate & Gardens to explore their beautiful gardens and taste their wines.
• Brunch: Enjoy brunch at the Kendall-Jackson Wine Estate or a local café.

Afternoon:

• Exploring Healdsburg: Spend some time in Healdsburg, visiting local boutiques, art galleries, and more wineries such as Rodney Strong Vineyards or Dry Creek Vineyard.

Evening:

• Early Dinner: Have an early dinner at one of Healdsburg’s top restaurants, like SingleThread (advance reservations required) or Barndiva.
• Drive to Airport: Head back to SFO or SMF for your departure flight.

Additional Tips:

• Reservations: Make reservations for wineries, restaurants, and activities well in advance, especially for popular spots.
• Transportation: Consider hiring a driver or joining a wine tour for a day to safely enjoy wine tastings.
• Weather: Check the weather and pack accordingly. Layers are a good idea, as temperatures can vary.

Enjoy your trip to California Wine Country!