A recent article in al-akhbar provides a remarkably detailed picture of the various towns and highways currently being struggled for between the Syrian Government and Rebel forces in Aleppo . I found the article from mint press news.
You can read the first two paragraphs to obtain a good understanding of which transit routes are currently important in relation to on-going battles. I think what this article captures that is really good though, is how the Turkish border is interacting with the current campaign. According to information from the border city of Azaz, Turkish authorities opened up the Bab al-Salam border crossing near the city to fighters in an unprecedented way. Also reported in al Akbar is that Turkish intelligence agents of Caucasian persuasion were sited (and according to some observers captured) in Aleppo, supplying rebels with intelligence on SAA movements. which were critical in holding defensive positions.
Upon seizing control of the towns of Bashkoy, Ratyan and Hardetneen in Aleppo’s northern countryside, the Syrian army retreated in Ratyan. Government sources say that this retreat came in response to opposition groups mobilizing forces from the Aleppo countryside and, indeed, from within Turkish territory. The army began to reinforce its positions in Bashkoy, Hardetneen and the neighborhood it still controls in Ratyan. The same sources said that improvement in the weather conditions would allow them to resume the attack and encircle the neighborhoods under opposition control in the city of Aleppo, and so lift the siege imposed on Nubl and al-Zahraa (Aleppo’s northern countryside) since July 2012.
Syrian army forces managed to infiltrate the two towns yesterday at dawn, but the battle intensified in Ratyan. Opposition groups (al-Nusra Front, al-Shamia Front, Hazm Movement and their allies) mobilized hundred of fighters to prevent the army from controlling it. Further, regime forces attacked the neighboring town of Bianoon in preparation for breaking the siege around Nubl and al-Zahraa, and cutting off the international road connecting Aleppo with Turkey through Azaz. This road is as good as blocked, even if the army does not reach it, because of the fighting going on there, which subsided yesterday night due to unstable weather conditions. But cutting off the international road near al-Zahraa does not prevent heavy reinforcements from reaching the battleground via Turkey. The border between Aleppo’s northern countryside and Turkey is still wide open, allowing the transfer yesterday of military and human reinforcements to the fighters in the vicinity of Nubl and al-Zahraa, and evacuating al-Nusra and its allies’ wounded to Turkish hospitals through the Bab al-Salam border crossing.