Mongolia’s flag includes a yellow Soyombo symbol on the hoist-side red stripe. The flag is a vertical triband: red at both outer sides and blue in the centre, with the Soyombo placed on the leftmost stripe.
The Soyombo is a traditional Mongolian national symbol made from geometric forms representing ideas such as fire, the sun, the moon, earth, water and the eternal sky. Its yellow colour is associated with Tibetan Buddhism, an important influence in Mongolian religious and cultural history.
The modern flag was adopted on 12 January 1992 after Mongolia’s transition away from the communist People’s Republic. An earlier version displayed a communist star above the Soyombo; that star was removed in 1992. Official colour standards were later established in 2011.
Tibet is a tempting wrong answer because Tibetan symbolism also uses Buddhist imagery, but Tibet does not have Mongolia’s national triband flag. Kyrgyzstan’s flag features a red field and a central sun, while Bhutan’s includes a dragon rather than a Soyombo.