Women in traditional costumes pose for photos in an alley in Chefchaouen, Morocco, on Aug. 24, 2019. Chefchaouen is a tourist destination in northern Morocco, known as Morocco's "blue city" for its blue walls and alleys.

A boys walks in an alley in Chefchaouen, Morocco, on Aug. 24, 2019. Chefchaouen is a tourist destination in northern Morocco, known as Morocco's "blue city" for its blue walls and alleys.

Tourists visit an alley in Chefchaouen, Morocco, on Aug. 24, 2019. Chefchaouen is a tourist destination in northern Morocco, known as Morocco's "blue city" for its blue walls and alleys.

Tourists visit an alley in Chefchaouen, Morocco, on Aug. 24, 2019. Chefchaouen is a tourist destination in northern Morocco, known as Morocco's "blue city" for its blue walls and alleys.

Children walk in an alley in Chefchaouen, Morocco, on Aug. 24, 2019. Chefchaouen is a tourist destination in northern Morocco, known as Morocco's "blue city" for its blue walls and alleys.

Tourists visit a souvenir stand in Chefchaouen, Morocco, on Aug. 24, 2019. Chefchaouen is a tourist destination in northern Morocco, known as Morocco's "blue city" for its blue walls and alleys. (Photos: Xinhua)

A girl is seen in an alley in Chefchaouen, Morocco, on Aug. 24, 2019. Chefchaouen is a tourist destination in northern Morocco, known as Morocco's "blue city" for its blue walls and alleys.