The Theatre Royal was built in 1805 in Bath, England to replace the Old Orchard Street Theatre. The building was designed by George Dance the Younger. In Persuasion, Charles invites his extended family to join him for a night a the theater: "I have been to the theatre, and secured a box for to-morrow night. A'n't I a good boy? I know you love a play; and there is room for us all" (Austen 233-234). Though he does not directly name the Theater Royal, it can be assumed that he was referring to this theater. 

The Isle of Wight is an island off the south coast of England where John Keats likely wrote the poem When I Have Fears That I May Cease to Be. He wrote this poem between January 22 and 31, 1818. He originally travelled here in order to write his longest poem, Endymion. 

Sources:

https://www.britannica.com/biography/John-Keats/The-year-1819

Moorgate is the street in London, England where John Keats was born on October 31, 1795. When he was a child, he moved in with his grandmother in Edmonton, and eventually moved to London to work as a junior house surgeon at Guy's and St. Thomas Hospitals. Near the end of his life, Keats went on a walking tour of Scotland, Ireland, and the Lake District with his best friend and fellow poet, Charles Armitage Brown. A few months before his death, he was accompanied by another friend, Joseph Severn, to Rome, Italy. On February 23, 1821, John Keats passed away in Rome.