Wat Rong Khun also known as White Temple it's a project of Thailand national artist Chalermchai Kositpipat. The construction began in 1997, the building of the temple have been severely damaged by an earthquake in May 2014.
Located 13km south of Chiang Rai.
The Black Temple also known as the Black House or Baan Dam was a project of Thailand national artist Thawan Duchanee who died on September 3 - 2014 at the age of 74.
It not so easy to find, take a look at the map below.
The nice Wat Klang Wiang Lanna style Temple constructed in 1432. The Wat Wang Chang and Wat Phra Sing are also very nice temples.
The famous Clock Tower of Chiang Rai is created by Chalermchai Kositpipat the artist who also created Wat Rong Khung.