It is definitely still open and going strong! Best way to get in touch is to call their listed number after 3pm or so. Closed on Mondays.
It looks like it's still open since I can find it on Resy for books in March. It's still located on P street and from the map on Resy still the same location. I will say it's hard to locate when walking down the street but there is a display box and ther bottom of the stairs to the restaurant that houses the daily menu. The only indication that it's Obelisk is the metal obelisk by the door at the top of the stairs.
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