Peak tourist season in Cambodia is from November to April, when the weather is dry. If you are looking for less crowds, visit between May and October, though you’ll have to deal with mid-afternoon showers. Cambodia presents a rich and complicated history, with various religious and cultural influences. You won't see everything in a week, but with the right plan, the most prominent destinations can be covered.
Start in Phnom Penh, the capital city. On your first day, visit the Royal Palace and the Silver Pagoda, and Temple of the Emerald Buddha. To get a sense of Cambodia’s history, one must acknowledge its darker side and pay respect to the countless people who lost their lives during the reign of Pol Pot. The Killing Fields of Choeung Ek and Tuol Sleng Genocide Museum are both key to understanding the history of the country under the Khmer Rouge. While visiting temples or memorials, dress conservatively. Everyone should have their shoulders and knees covered.
After a day or two in the capital, head to Siem Reap, the tourist capital of the country. Enjoy the local markets before heading to Angkor Archaeological Park. With over 1,000 temples in its vicinity, you should extend this excursion to two days. Invest in a three-day pass. Then, for the next three days, I suggest heading to Battambang to experience a more rustic countryside. Take a tuk-tuk to Wat Banan, the mini Angkor Wat. Or perhaps visit the Koh Rong Island for a slice of the coastal life. Given its virgin beaches, it is the best place to unwind and relax before travelling back to India.
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