noun
memorial hall; museum (commemorating a person or event)
Typically a building or facility dedicated to preserving the memory of a notable person, historical event, or achievement. Often used in proper names like 〇〇記念館.
来週、漱石記念館に行く予定です。
I plan to go to the Soseki Memorial Museum next week.
この記念館は、戦争の記憶を伝えるために建てられ
This memorial hall was built to pass on the memory of the war.
美術館 is an art museum, focusing on art collections and exhibitions, not necessarily commemorative.
Compound of 記念 (commemoration, memory) and 館 (hall, building). The reading is standard on'yomi.