Beneath the tourist bustle of Edinburgh’s Royal Mile, a warren of steep, narrow alleyways sits sealed in permanent dusk — a genuine 16th- and 17th-century street of tenement housing, shops and workshops that was built over rather than demolished, and now survives frozen in time under the City Chambers. It takes its name from Mary King, a 17th-century Edinburgh burgess and merchant who lived and worked there, when the close was still an open-air street rising several storeys, its poorer residents crammed into the damp lower levels while wealthier households took the upper floors.

The close’s darkest chapter is the 1645 plague, which killed roughly half the city’s population within months. Popular legend holds that Mary King’s Close was walled up with the sick and dying still inside and simply abandoned — a dramatic story with almost no documentary support. What actually happened was grimmer in a quieter way: the area was placed under quarantine, food and water brought to residents, until the last of them eventually left and the close was gradually abandoned. In the 1750s the new Royal Exchange — now Edinburgh’s City Chambers — was built on top of the lower storeys of several closes, including Mary King’s, entombing the street below modern ground level while leaving much of its structure intact. A handful of residents lived and worked on in the surviving lower sections; saw-maker Andrew Chesney, the close’s last recorded resident, was forced out “under duress” by the city in 1897 but kept working there until 1902. The close then sat largely forgotten — used for storage and municipal purposes — until it was progressively opened up and launched as a fully guided visitor attraction, The Real Mary King’s Close, in April 2003.

The close’s best-known ghost is a little girl nicknamed “Annie.” In the 1990s, Japanese psychic Aiko Gibo visited and reported being overwhelmed with grief in one particular 17th-century room, sensing a child separated from her parents after her mother caught the plague. Gibo said the girl told her she had lost her favourite doll; Gibo bought a replacement and left it in the room. Word spread, and visitors from around the world have been leaving dolls and toys in the same corner ever since — “Annie’s Room” is now one of the close’s signature stops. A second recurring figure, an unnamed heavyset “large man,” has been linked by some psychics and staff to Major Thomas Weir, the “Wizard of West Bow” — a real 17th-century militia officer executed in 1670 after confessing to witchcraft — though others attribute the same sightings to Andrew Chesney instead.

The close has drawn sustained attention from both television and academia. Most Haunted filmed a studio episode there in 2004 and returned for a three-day live Halloween broadcast on Sky Living in 2006; Ghost Hunters International investigated in an episode first broadcast in January 2008. The Ghost Club ran its own investigation and reported EVP recordings responding to direct questions from staff. More unusually for a site in this database, the close was also the subject of a genuine academic study: Dr Caroline Watt of the University of Edinburgh’s Koestler Parapsychology Unit ran a formal experiment there around 2001, finding that more than 40% of participants reported some kind of unusual experience — a measure of subjective reporting rather than proof of anything paranormal, but a rare instance of a UK “haunted” site being studied by an actual university research unit rather than only TV crews and ghost-tour operators.

Being upfront about the evidence: none of this amounts to independent scientific proof. The Ghost Club’s EVP recordings are open to interpretation, the Watt study measured subjective experience rather than confirming a cause, and a 2008 infrared photograph showing a translucent figure in a doorway — taken by the close’s own general manager, alone, after hours — has never been authenticated. Readers weighing how much stock to put in any of it may find our guide to how ghost hunting evidence gets evaluated useful context.

Ghost stories aside, Mary King’s Close would earn its place in this database for the history alone: an entire vertical slice of a 17th-century Scottish street, complete with fireplaces, close-mouths and worn stone stairs, preserved by accident under a working municipal building for nearly 300 years and now one of the most visited heritage attractions in Edinburgh’s Old Town.