1.0Medievalists.nethttps://www.medievalists.netMedievalists.nethttps://www.medievalists.net/author/charlemagne/rich600338<blockquote class="wp-embedded-content" data-secret="YZTWHJqmiq"><a href="https://www.medievalists.net/2012/08/a-defence-installation-of-the-developing-lithuanian-state/">A defence installation of the developing Lithuanian state</a></blockquote><iframe sandbox="allow-scripts" security="restricted" src="https://www.medievalists.net/2012/08/a-defence-installation-of-the-developing-lithuanian-state/embed/#?secret=YZTWHJqmiq" width="600" height="338" title="“A defence installation of the developing Lithuanian state” — Medievalists.net" data-secret="YZTWHJqmiq" frameborder="0" marginwidth="0" marginheight="0" scrolling="no" class="wp-embedded-content"></iframe><script type="text/javascript"> /*! This file is auto-generated */ !function(c,d){"use strict";var e=!1,o=!1;if(d.querySelector)if(c.addEventListener)e=!0;if(c.wp=c.wp||{},c.wp.receiveEmbedMessage);else if(c.wp.receiveEmbedMessage=function(e){var t=e.data;if(!t);else if(!(t.secret||t.message||t.value));else if(/[^a-zA-Z0-9]/.test(t.secret));else{for(var r,s,a,i=d.querySelectorAll('iframe[data-secret="'+t.secret+'"]'),n=d.querySelectorAll('blockquote[data-secret="'+t.secret+'"]'),o=new RegExp("^https?:$","i"),l=0;l<n.length;l++)n[l].style.display="none";for(l=0;l<i.length;l++)if(r=i[l],e.source!==r.contentWindow);else{if(r.removeAttribute("style"),"height"===t.message){if(1e3<(s=parseInt(t.value,10)))s=1e3;else if(~~s<200)s=200;r.height=s}if("link"===t.message)if(s=d.createElement("a"),a=d.createElement("a"),s.href=r.getAttribute("src"),a.href=t.value,!o.test(a.protocol));else if(a.host===s.host)if(d.activeElement===r)c.top.location.href=t.value}}},e)c.addEventListener("message",c.wp.receiveEmbedMessage,!1),d.addEventListener("DOMContentLoaded",t,!1),c.addEventListener("load",t,!1);function t(){if(o);else{o=!0;for(var e,t,r,s=-1!==navigator.appVersion.indexOf("MSIE 10"),a=!!navigator.userAgent.match(/Trident.*rv:11\./),i=d.querySelectorAll("iframe.wp-embedded-content"),n=0;n<i.length;n++){if(!(r=(t=i[n]).getAttribute("data-secret")))r=Math.random().toString(36).substr(2,10),t.src+="#?secret="+r,t.setAttribute("data-secret",r);if(s||a)(e=t.cloneNode(!0)).removeAttribute("security"),t.parentNode.replaceChild(e,t);t.contentWindow.postMessage({message:"ready",secret:r},"*")}}}}(window,document); </script> This defence installation from the 12th and 13th centuries belongs to the most important fortified area of the newly developing Lithuanian state. It extended about 50 kilometres from east to west, and was built as a defence against the Polotsk-Pskov duchies and the Livonian Order.http://www.medievalists.net/wp-content/uploads/2012/08/80013.jpeg