Der Rosenkavalier ★ ★ ★ ★ ★ Eugene Onegin ★ ★ ★ ☆☆ Garsington Opera started life in the grounds of a 17th-century Oxfordshire manor house owned by an opera lover, but the company was sent into exile when his descendants decided they wanted to enjoy their home without sharing it with the public; they were also sick of dealing …