Berlin remained the final open crossing from the more and more militarised and airtight "internal-German" border. On 13 August 1961, the East German (GDR) leadership closed the border just months after East German chief Walter Ulbricht claimed inside a push convention "Niemand hat die Absicht eine Mauer zu errichten" (nobody https://roof10753.ktwiki.com/964509/5_simple_statements_about_rum_explained