On March 23, 2019, the Lebanese anti-Hizbullah Al-Modon daily reported that during February 2019, Iran had evacuated its bases and weapons depots near the Damascus International Airport.It explained that this move was based on understandings with Russia and was aimed at preventing further attacks by Israel in the region. In accordance with these understandings, it added, Iran would be able to continue to send fighters, light military equipment, and logistical support via the Damascus airport, but that precision and long-range missiles, according to the assessment of sources cited in the report, would from now on be sent to Syria via Iraq or Lebanon.
The report added, citing a source described as close to the Damascus airport administration, that most of the Iranian missiles at the evacuated bases had been transferred to commands of the Syrian Army's Fourth Division in the Rif Dimashq Governorate, and that some of the equipment and ammunition were transferred to bases of the Syrian Army First Division as well as to the Al-Mezzeh Military Airport southwest of Damascus.
Damascus International Airport (Source: Syria-scope.com, April 4, 2018)
Also according to the report, Iran is planning to establish a new military airport near Al-Kiswah in the west of the Rif Dimashq Governorate, and that it has recommenced activity at the Al-Dimas Airport in the same region, near the Syria-Lebanon border. The new military airport will be used, inter alia, to launch drones into Israel for fighting and surveillance purposes, and as a Hizbullah intelligence base.
The following is a translation of the main points of the March 23 Al-Modon report:
Iranian Bases, Weapons Are Being Transferred From Damascus Airport To Other Bases – For Fear Of Israeli Attacks
"A special source has confirmed to Al-Modon that the Iranian militias have completed the February  evacuation of their depots and intelligence centers located three kilometers from Damascus International Airport, in accordance with understandings [arrived at] with the Russian side, with the aim of protecting the airport from further [Israeli] attacks. According to the source, the agreement [with the Russians] states that Iran will stop sending prohibited weapons and ammunition, such as precision and long-range missiles, via Damascus International Airport, but will be permitted to continue to send fighters, light military equipment, and the logistical support required by the Shi'ite fighters fighting in Syria [via this route]. The source, who is close to the [Damascus] airport administration, stated that the Iran-Russia agreement would lead to Russia-Israel coordination, according to which [Israel] would stop bombing the airport and its environs during the evacuation activity.
"According to the source, the evacuated positions included more than nine large depots of weapons, ammunition, and long-range missiles. Additionally, an intelligence center near the airport, facing Eastern Ghouta, was evacuated, as were a center spying on wireless communications and an operational command center. The evacuated depots' [inventory] was divided among military bases east, west, and north of Damascus, and most of the missiles were transferred to [Syrian Army] Fourth Division command posts, situated on the broad mountain range in the west of Rif Dimashq Governorate Likewise, some of the weapons, ammunition, and logistical equipment were transferred to bases of the First Division; of all the regime forces, this division is the most closely affiliated with Iran, while some of the medium and light weapons and equipment were transferred to the Al-Mezzeh Military Airport."
From Now On, Iran Will Send Military Equipment Via Airports In Iraq Or Lebanon, And From There Overland To Syria
"Among the evacuated positions is the 'Glass House'– the largest Iranian base near Damascus International Airport. Israel, which has disseminated photos of it, claimed nevertheless that it has been empty for months, with no notable activity going on there. But the Iranians, according to sources [who spoke to Al-Modon], have left one underground command at the Glass House, for receiving visiting Iranian personnel arriving in Damascus via the airport for temporary [stays] until the route to their destination is secured.
"Despite the evacuation of dozens of Iranian military positions around the international airport, there remain groups of fighters subject to the local and foreign Shi'ite militias; these groups are located in the government factories and in the large abandoned hangars around the airport, facing Eastern Ghouta. Around these places are air defense bases, that serve as dormitories and as training centers [for fighters]...
"The source assessed that Iranian equipment [destined for Syria] will from now on be sent to airports in Iraq and from there will be transported overland to Syria, or via Beirut's Rafic Hariri International Airport and from there [to Syria] via legal and illegal passages controlled by Hizbullah and other groups subject to Iran."
Iran Seeks To Build A Military Airport West Of Rif Dimashq, And Is Already Operating Another, As A Base For Fighting And Espionage Against Israel
"The operation to evacuate the Iranian depots near Damascus airport was carried out at the same time as discussions [were underway] about Iran's intention, in agreement with the Russians, to establish a new military airport in western Rif Dimashq near the town of Al-Kiswah. Most of the Shi'ite, Iranian, and Lebanese militias are located there. The aim is to move the activity at Al-Mezzeh Military Airport to the new airport, which will be under full Iranian control and will serve military purposes, instead of moving it to Damascus International Airport.
"Sources also told Al-Modon that the Iranian militias had operated Al-Dimas Airport [used for] gliders and that it was not in operation since being bombed by Israel in 2014... [sometime after which] it became a training base and living quarters for local and foreign militias belonging to the regime. Al-Dimas Airport began operating [once more as an airport] in early 2019 in coordination with [Syrian] Air Forces units. According to Al-Modon's sources, Iran has designated it [i.e. Al-Dimas Airport, as the site] for developing drones for fighting and for surveillance of the Golan and of positions near Israel. This is in addition to using it as an intelligence base [for holding] command meetings with the participation of Hizbullah commanders, due to its proximity to the Syria-Lebanon border..."