Zahir Mosque, State mosque in Alor Setar, Kedah, Malaysia

Zahir Mosque is a Sunni state mosque in Alor Setar, Kedah, built from 1912 to 1915. Its central prayer hall measures 62 by 62 feet and is surrounded by an 8-foot-wide veranda with four porches, each topped by a dome. Five main domes represent the Five Pillars of Islam, and the site covers about 124,412 square feet.

Construction began on 11 March 1912 under Tunku Mahmud ibni Sultan Ahmad Tajuddin Mukarram Shah, on ground that was the burial site of Kedah warriors killed resisting the Siamese invasion of 1821; 1,489 martyrs are said to be buried there. Sultan Abdul Hamid Halim Shah opened the mosque on Friday, 15 October 1915, after Tunku Mahmud read the Friday sermon and the Sultan led the prayer. The design drew on the Azizi Mosque of Langkat, North Sumatra.

The mosque is also called Masjid Raja (Royal Mosque) because it stands beside the Istana Pelamin palace grounds. Its annual state Qur'an-reading competition is held on the premises. Before the call to prayer, the Nobat drums of the neighbouring Balai Nobat were once played, followed by the adhan.

The mosque is located along Darul Aman Highway and is free to visit without entrance fees. The best time to visit is outside prayer times, when you can explore the interior more freely.

The site was a burial ground for Kedah warriors killed in the 1821 Siamese invasion; 1,489 martyrs are said to be interred beneath the mosque, including 470 who fell defending the Balai Besar. The five main domes stand for the Five Pillars of Islam.