Here's an ideal itinerary for 6 days in Thailand:

Day 1: Arrival in Bangkok

• Arrive at Suvarnabhumi Airport and check into your hotel
• Take a stroll around the vibrant streets of Bangkok, visit the famous Khao San Road and try some street food
• Visit the Grand Palace and Wat Phra Kaew, two of the most iconic landmarks in Bangkok

Day 2: Exploring Bangkok

• Start your day with a visit to Wat Arun, also known as the Temple of Dawn
• Take a boat ride along the Chao Phraya River and explore the local markets
• Visit Wat Pho, home to the famous reclining Buddha statue
• In the evening, head to one of the many rooftop bars in Bangkok for a stunning view of the city skyline

Day 3: Ayutthaya Day Trip

• Take a day trip to Ayutthaya, the ancient capital of Thailand
• Explore the ruins of the old city, including the famous Wat Mahathat and Wat Yai Chai Mongkol temples
• Enjoy a traditional Thai lunch by the river before heading back to Bangkok

Day 4: Chiang Mai

• Fly to Chiang Mai, a charming city in northern Thailand
• Visit the famous Doi Suthep temple, located on a mountain overlooking the city
• Explore the night markets and sample some delicious northern Thai cuisine

Day 5: Elephant Sanctuary

• Spend the day at an elephant sanctuary, where you can interact with these gentle giants in a responsible and ethical way
• Learn about the history and culture of elephants in Thailand while feeding and bathing them
• Return to Chiang Mai in the evening for a relaxing dinner

Day 6: Departure

• Take a morning flight back to Bangkok and spend your last few hours shopping for souvenirs or exploring any sights you may have missed
• Depart from Suvarnabhumi Airport with unforgettable memories of your trip to Thailand

I hope this itinerary helps you plan your trip to Thailand!