Symbols & general
Why is Nepal's flag triangular?
Nepal has the only national flag in the world that is not a rectangle. It is made of two stacked triangular pennants, derived from the separate flags of two ruling houses. The triangles also evoke the Himalayan peaks, while the sun and moon symbolise permanence.
The flag's geometry is defined precisely in the constitution — the only such mathematically-specified flag.
Sources & data note
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