A 4-day domestic tour to Somnath, Dwarka, and Porbandar, starting from Ahmedabad, can include a day for Dwarka sightseeing, a day to travel to Somnath via Porbandar, and a final day for Somnath exploration before returning to Ahmedabad. 

Here's a possible 4-day itinerary:

Day 1: Ahmedabad to Dwarka

• Morning: Depart from Ahmedabad and drive to Dwarka (approx. 8 hours). 
• Afternoon/Evening: Check into your hotel and visit the Dwarkadhish Temple, Bet Dwarka, and Gopi Talav. 
• Night: Attend the evening aarti at Dwarkadhish Temple and stay overnight in Dwarka. 

Day 2: Dwarka to Somnath (via Porbandar)

• Morning: Have breakfast and check out of your Dwarka hotel. 
• Afternoon: Drive to Porbandar (approx. 1.5 hours) and visit Kirti Mandir, where Mahatma Gandhi was born. 
• Afternoon: Continue to Somnath (approx. 2.5 hours). 
• Evening: Check into your Somnath hotel and visit the Somnath Temple and Bhalka Tirth. 

Day 3: Somnath Exploration

• Morning: Explore Somnath Temple, Triveni Sangam, and Geeta Mandir.
• Afternoon: Visit the Junagadh Gate and other nearby attractions.
• Evening: Watch the light and sound show at Somnath Temple. 

Day 4: Somnath to Ahmedabad

• Morning: Have breakfast and check out of your Somnath hotel.
• Afternoon: Drive back to Ahmedabad (approx. 7.5 hours).
• Evening: Depending on your departure time, you can visit some local attractions in Ahmedabad like Kankaria Lake, Sabarmati Ashram, or Akshardham Temple (closed on Mondays).
• Night: Depart from Ahmedabad by train or flight.