Míngtáng 明堂 Hall of Light (or Bright Hall)
Of course, there is a sacred building to use for imperial ceremonies in the history of ancient Chinese culture but for us now more important is the Hall of Light mentioned in Ge Hung’s (283-343) Baopu zi and its location one inch behind the area between the eyebrows. More detailed description can be found in the article written by Martina Darga.
I cannot add to this note much enough. In the acupuncture textbook this is the place for Yìntáng 印堂 (Hall of Impression) which corresponds to the area ascribed to the ‘third eye’ by many traditional cultures, and has been classified by some qigong authors as the location of the upper dāntián 丹田. That is an extra point, it does not belong to Rèn Mài 任 脈 (The Conceptor Vessel) or more exactly to Dū Mài 督 脈 (The Governor Vessel).
Speaking on many traditional cultures let us make one step into the Indian heritage of yoga. The region between two eyes is called ājñā chakra (the sixth chakra of classical set of seven or eight in Kuṇḍalinī yoga) and followers denote it like the inner mind’s eye to sense subtle energies and to be a gateway flooded with infinite wisdom, insight, and inspiration. So far so good.
Inside martial art practitioners’ milieu and Dim-Mak 點脈 (diănmài) reference books (Erle Montaigue and Wally Simpson, for example) this acupoint is translated ‘decorating place’ and described like causing KO and sometimes called ‘the old evangelist’s point’ which sounds curious enough.
The big colour picture of the ancient architecture would be probably the better illustration here.