Tehran unlike most big cities has left its so called "downtown" to ruins in the past 40 or so yrs...happily though in recent years some of the old galleries such as "bAghe NegarestAn " located in North west corner of BahrestAn has been restored and done so very skillfully...the other great one such as "emArate Masiudieh" at the south east corner of bahArestAn is going through the work and not opened to public yet...I was just lucky to be in "bAghe NegArestAn" before it opened and got to see it all by myself few weeks ago...it is open to public now.