Russian guitar

The Russian guitar, a seven-string acoustic guitar tuned to the Open G tuning, arrived in the beginning of the 19th century in Russia, most probably as a development of the cittern, kobza and torban. It is known in Russia as the semistrunnaya gitara (семиструнная гитара), which translates to seven string guitar or affectionately as the semistrunka (семиструнка).
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7 strings; popularised at the beginning of the 20th century.