Sanam Luang, officially Thong Sanam Luang, is a 74.5 rai open field and public square in front of Wat Phra Kaew and the Grand Palace, Bangkok, Thailand. Sanam Luang is in the Phra Nakhon District, the historic center of Bangkok. From Wikipedia
The relic's arrival marks the Thai king's 72nd birthday and 50 years of diplomatic relations between Thailand and China.