Latvian President Raimonds Vejonis (3rd L) and Estonian President Kersti Kaljulaid (4th L) attend the celebration ceremony at a former border crossing between Valka in Latvia and Valga in Estonia, on Dec. 21, 2017. The presidents of Baltic neighbors Latvia and Estonia met on Thursday to mark their countries' first decade in the Schengen Area. (Xinhua/Janis)