The Onyx Hotel offers posh rooms and proximity to some of the most widely visited Boston attractions. Whether you want to attend a Celtics game the Fleet Center or watch the sidewalk performers in Faneuil Hall, you won’t have far to go from your room at the Onyx. The black, beige and ruby red rooms of the Onyx are full of comfortable yet elegant furnishings. The checked carpets found in these rooms make an instant impression, while the rich fabrics that surround you will promote instant relaxation. After a busy day in Boston, you can slip into a downy bathrobe and seat yourself in a soft suede chair. Pop culture fans might want to check into the Britney Spears Foundation Room, decorated by her mother to look like the singer’s bedroom at home in Louisiana. Ten percent of the cost of this room goes to the Britney’s foundation, which supports kids in need. Taking its commitment to fine design to the next level, the Onyx Hotel’s stunning Ruby Room offers meals and cocktails in a refined setting. Named in honor of its ruby red color scheme, this establishment features a bouquet of hanging red lights above a bar of black granite.