Turkish-Syrian border

''At any time if the United States truly wanted to strike an irreparable blow at ISIS forces, it could simply seal off the Turkish border across which the summation of ISIS’ supplies, fighters, weapons, and vehicles flow. By securing the Turkish-Syrian border to the north, and the Jordanian-Syrian border in the south, the United States could strangle ISIS out of existence in a month, if not sooner.
 * — Tony Cartalucci, US Complains as Russia Bombs Its Terrorists - New Eastern Outlook, October 1, 2015

Open borders for rebels

 * Syrian rebels say reinforcements get free passage via Turkey - Today's Zaman, February 18, 2016
 * ''At least 2,000 Syrian rebel fighters have re-entered the country from Turkey over the last week to reinforce insurgents fending off an assault by Syrian Kurdish militias, rebel sources said on Thursday.
 * ''The rebel fighters, with weapons and vehicles, have been covertly escorted across the border by Turkish forces over several nights before heading into the embattled rebel stronghold of Azaz, the sources said. "We have been allowed to move everything from light weapons to heavy equipment mortars and missiles and our tanks," Abu Issa, a commander in the Levant Front, the rebel group that runs the border crossing of Bab al-Salam, told Reuters, giving his alias and talking on condition of anonymity. "There is tight security on the four-hour drive from one border crossing to the other," he added, saying rebels being transported excluded the hardline Jabhat al-Nusra Front fighters and other jihadist groups.
 * ''A Turkish security source confirmed fighters had crossed the border but put the numbers at 400-500 and the British-based Syrian Observatory for Human Rights, which tracks violence across the war torn-country, also said hundreds had crossed.

Turkish oil trade with ISIS

 * ''Moved to Turkish oil trade with ISIS