20 Euro KM#217 Silver Ag 925 Quality proof Diameter 38.61 mm Weight 28.28 g. Subject: Struve Geodetic Arc. The obverse of the coin features Vytis in the centre, surrounded by a stylised meridian arc, the inscription UNESCO PASAULIO PAVELDAS, LIETUVA, 2015 (UNESCO WORLD HERITAGE, LITHUANIA, 2015), denomination (€20) and the mintmark of the Lithuanian Mint. The reverse of the coin features an artistic composition that seeks to immortalise globally-significant achievements in science and technology while studying the Earth’s meridian arc, which covers 10 nations. The Struve Geodetic Arc is named in honour of F. G. W. Struve, a scientist who performed geodetic measurements through the triangulation method and systemised the results. The inscription STRUVĖS GEODEZINIS LANKAS (STRUVE GEODETIC ARC) is arranged in a semicircle. Designed by Tadas Žebrauskas. Mintage 3,000 pcs. Issued 11-05-2015. The coin was minted at the state enterprise Lithuanian Mint.