Beginning in 1968, Benjamin Mazar excavated the southern wall of Herod's Temple down to its original foundation.  The wall perpendicular to the southern wall was not original to Herod's Temple.  Visible midway along the southern wall is a stairway that provides access to a set of gates leading under the outer court and eventually up into it.  (Source: http:// www.israel.org/mfa/jerair/ jerex.html) 
 
 

The stairs, c. 200 ft. wide, led up to a set of double gates, called the Double Huldah Gates. 

To the east of the Double Huldah Gates was situated a set of  three gates, called the Triple Huldah Gates.  Leading up to these gates was a narrower stairway (50 ft. wide).  Before they were closed up, the Triple Huldah Gates led into the so-called "Solomon's Stables."  The Huldah Gates would lead underground into the outer court.