As Malaysia is a Muslim country, mosques can be found everywhere. One of the most famous ones in KL is Masjid Negara (the National Mosque). It was built in 1965 and can accommodate 15,000 worshippers.
This photo is of the Mihrab. It's a semicircular niche in the wall at the front of the mosque and it indicates the direction of Mecca, which is the direction that worshippers face when praying. The Imam (the one who leads the prayers) stands close to the Mihrab and everyone else congregates in rows behind him.
As can be seen here, the Mihrab is usually quite intricately designed and decorated with Islamic motifs.