1. Chiang Saen is an ancient city located in the northern province of Chiang Rai, Thailand. It was founded in the 7th century and served as the capital of the Lanna Kingdom until the 13th century. Today, visitors can see the remains of ancient city walls and temples, including Wat Chedi Luang and Wat Pa Sak. The Chiang Saen National Museum also houses a collection of ancient artifacts and exhibits.

2. The working time and phone numbers for attractions in Chiang Saen may vary, but the Chiang Saen National Museum is open daily except for Mondays from 9:00 AM to 4:00 PM. Their phone number is +66 53 784 124.

3. Admission to the Chiang Saen National Museum is 100 Thai Baht per person. Transportation options to Chiang Saen include hiring a private car or driver, taking a taxi, or taking a local bus from Chiang Rai city. The bus ride takes about an hour and costs around 30 Thai Baht.