The mall's second major renovation replaced the open-air Plaza Court with a 3-level, fully-enclosed structure. Construction commenced in February 1979, with the new and improved Plaza Court being officially dedicated in August 1980. The facility housed forty-seven restaurants and boutiques.
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The new Plaza Court (in medium gray) was the first phase of a major renovation and expansion of LENOX SQUARE. As part of this project, Macy's (Davison's) and Rich's were enlarged. A second stage of construction brought a luxury hotel and office tower. Retail space was also added to the Plaza Court (in light gray). When construction dust settled in September 1988, the mall covered approximately 1.3 million square feet and housed over 200 stores and services. 

Please pardon the quality. Above and below are two snapshots from one of my first visits to LENOX SQUARE, in 1986. These show the original, 3-level Plaza Court.

In this photo, we see the entrance to the mall's first Macy's (nee' Davison's, now Bloomingdale's).