The complex at Tabriz is reportedly Iran's second missile base housed in a silo, and its location in northwestern Iran suggests parts of Eastern and Central Europe may be within range of Iranian missiles. [1] According to analyst Sean O'Connor from Air Power Australia, transporter erector launchers (TEL) for the Shahab-1, Shahab-2 and potentially Shahab-3 missiles appear to exist at the site. [2] O'Connor also notes that Iran constructed two hardened silos at the base that probably contain Shahab-2 or Shahab-3 missiles. [3] Additionally, the mountainous topography around Tabriz and the hardened underground silos would increase the survivability of the missiles. An Israeli source purports that the Tabriz launch area is approximately 50,000 km2. [4]

Sources:
[1] "Bericht: Iranische Nuklear-Raketen Koennten Berlin Erreichen," [Iranian nuclear missiles could reach Berlin], Handelsblatt, 16 December 2005, www.handelsblatt.com; Jeffrey Lewis, "Suspected Missile Site Near Tabriz, Iran," Arms Control Wonk Blog, 1 February 2009, www.armscontrolwonk.com.
[2] Sean O'Connor, "Iranian Missile Silos," IMINT & Analysis, 20 February 2008, geimint.blogspot.com.
[3] Sean O'Connor, "Iranian Missile Silos," IMINT & Analysis, 20 February 2008, geimint.blogspot.com.
[4] Uzi Rubin, "New Developments in Iran's Missile Capabilities: Implications Beyond the Middle East," Jerusalem Center for Public Affairs, 25 August 2009, www.jcpa.org.