The Cainhurst Summons can be found on a gurney in Iosefka's Clinic, in the room at the top of the stairs from the 1st Floor Sickroom lamp. Players must first unlock the shortcut to Iosefka's Clinic from the Forbidden Woods.
- The fastest way to reach the obelisk is to unlock the Witch's Abode lamp and walk from there. It will be at the bottom of the hill.
- Use of the Summons requires that the Witch of Hemwick boss has been killed.
- As it is addressed to "you" specifically, this summons may be the cause for the Hunter's arrival in Yharnam.
- This is somehow a reference to Bram Stoker's Dracula, as Jonathan Harker also received a letter summon and was transported to the castle in a stagecoach.