Mehter is the Ottoman military bands are thought to be the oldest variety of military marching band in the world. It is believed that the first "mehter" was sent (seven centuries ago) to Osman Gazi by the Seljuk Sultan Alaeddin III as a present along with a letter that salutes the newly formed state . From then on every day after the afternoon prayer; "mehter" played for the Ottoman ruler. The notion of a military marching band, such as those in use even today, began to be borrowed from the Ottoman Empire in the 16th century. In 1911, as the empire was beginning to collapse, the director of Istanbul's military museum attempted a somewhat successful revival of the tradition, and by 1953, the tradition had been fully restored as a band of the Turkish Armed Forces. Today, the music of the mehters is largely ceremonial and considered by many Turks as a stirring example of heroism and a reminder of Turkey's imperial past. Today, Mehter Troop (Mehter Bölüğü) is a band of the Turkish Armed Forces and it performs at the Military Museum (Askeri Müze) in Istanbul. The sound of the Ottoman military band is characterized by an often shrill sound combining bass drums, horns (boru), bells, the triangle and cymbals (zil), among others. It is still played at state, military and tourist functions in modern Turkey by the Mehter Band and the troops that accompany. Mehterân usually play classical Turkish music such as peşrev, semai, nakış, cengiharbi, murabba and kalenderi. Most of the music played by mehterân is Turkish Folk Music with heroic themes from the Ottoman frontiers. Melodies and lyrics are written in Mehterhane (the house of Mehter).