Crossword Puzzle Artifacts of the past

Clue: Artifacts of the past

Treasury offering of the past (EBOND with 5 letters)
River past Thebes (NILE with 4 letters)
Gets past a last difficulty ... or a hint to this puzzle's theme (ROUNDSTHECORNER with 15 letters)
Theater offering (e.g. DRAMA with 5 letters)
Theater offering, sometimes (DRAMA with 5 letters)
Theater offerings (e.g. DRAMAS with 6 letters)
Movie theater offering (FEATUREFILM with 11 letters)
Theater box office choice (BALCONYSEAT with 11 letters)
Bolshoi Theatre offering (OPERA with 5 letters)
National Theatre of Japan offering (KABUKIDANCE with 11 letters)