Day 1: Bangkok – Khao Yai (D)
Depart Bangkok for Saraburi. Visit Phra Buddha Badh with its shrine of the holy footprint of Lord Buddha and have lunch at a local restaurant (own expense). Continue to Khao Yai National Park. En route, view Wat Theppithak with its huge seated Buddha located on a hillside and visit the fruit market at Klang Dong. Dinner concludes your day.
Overnight: The Greenery Resort in Khao Yai
Day 2: Khao Yai – Korat (B, L, D)
After breakfast, start with a visit to the Krong Keo waterfalls; see the original bamboo suspension bridge and Haew Suwat falls. Depart for Korat and visit Thao Suranaree Memorial, built to commemorate the exploits of Khunying Mo, wife of the town’s second in command, who rallied her people to defeat Laotian invaders in 1826 under the reign of King Rama III.
Visit Wat Sala Loi, with its main chapel constructed in the shape of a Chinese junk using local earthen tiles. After a restaurant lunch, continue to Pimai to visit the museum and the magnificent Khmer temples, considered the 'Angkor Wat of Thailand.' Later you'll return to Korat for dinner at your accommodation.
Overnight: Dusit Princess Korat or similar
Day 3: Korat – Surin (B, L, D)
Following breakfast, visit Daan Kwian village, famous for its earthenware. Continue to Prasat Phnom Rung, the most important Khmer temple in Thailand. Situated on a hill, the monumental staircase is stunning and the sanctuary is one of the best examples of Khmer architecture. Visit Prasat Muang Tham, a Khmer temple even older than Prasat Phnom Rung, with many well-preserved bas-reliefs.
After lunch at a restaurant in Prakhon Chai, proceed to Surin to tour Prasat Hin Sikhoraphum before dinner at your accommodation.
Overnight: Thong Tarin or similar hotel in Surin
Day 4: Surin – Bangkok (B, L)
Eat breakfast and depart for Si Saket, with a stop at Prasat Wat Sa Kamphaeng Yai, the largest of the region's Khmer ruins. The 11th-century site comprises three stupas facing east and features the Bapua style; it served as a shrine for Lord Shiva before changing into a Mahayana Buddhist temple.
Continue to Prasat Wat Sa Kamphaeng Noi, used for religious purposes and also serving as a community hospital in the 13th century. You'll drive to Ubon Ratchathani for a restaurant lunch at midday, then proceed to Ban Pa Ao village. Continue to the Ban Kan Lueang archaeological site situated in Wat Ban Kan Lueang and excavated in the 1990s.
In the afternoon, you're taken to Ubon Ratchathani Airport for your onward flight to Bangkok (not included), where you're then transferred to your hotel.