To my surprise, the Regency Center was built in 1970. I always thought that was likely built around 1980, when the Marriott Hotel went in. However, in that Late 70's memory I shared, I can remember a fairly significant building that caught my eye, and that must have been it. After that time period, I have no memories of the I-680/Dodge interchange until around 1989, when my family moved across town, and we suddenly were passing through that interchange more frequently. I have fuzzy memories of Westroads Mall as a kid, though.
Anyways, by 1989, most of the office buildings in Old Mill existed, as they were mostly constructed in the early 80's (makes sense, as I don't remember any of those going up). However, as I remember, much of Miracle Hills went up post-1989 (which I witnessed).
In fact, I can remember the black, half moon-shaped First National Bank going up on the corner of 114th & Dodge. (I've included a picture of how nice it once looked on the corner, before they built the elevated expressway through. Now does my griping about that elevated expressway make sense? Look how nice the slick, curving architecture used to be featured w/ a green lawn, w/out obstruction, from that corner.) Surprisingly so, the Miracle Hills Golf Course was put-in in 1940. I'm guessing that Miracle Hills Parkway must have been strung through in 1985, as nothing existed along that parkway until that time.
To think this is basically the center of town now. Any thoughts & discussion is appreciated.

