Wikipedia:Notability (local interests)
A local interest is a subject that is likely only to be known by and only to be of interest to those within a limited geographical area, such as a city, town, village, metropolitan area, or other similar localized region. Articles on local interests are perfectly acceptable for inclusion on Wikipedia. But they must meet varying guidelines pertaining to in-depth, on-going, non-trivial coverage.
Local interests may include, but are not limited to, people whose function involves one area (e.g. mayors), businesses that primarily attract customers in the local area (e.g. corner stores or family-owned restaurants), schools, hospitals, places of worship, cemeteries, parks, or infrastructure.
Subjects that simply reside in a single location, but are well-known to a national or international audience are not considered to be local interest. For example, Walt Disney World Resort, though it is found in the Orlando, Florida area, is not a local interest of Orlando, because it attracts tourists from around the world. The Taj Mahal is found in Agra, Uttar Pradesh, India, but has an iconic status around the world, far beyond Agra.
Local sources
A local source is a source of information that is marketed to a limited geographical audience. These include, but are not limited to, newspapers, community papers, magazines, and journals representing a local city, town, or region, local television and radio stations (and their associated websites), and websites providing media to an area.
Local sources are considered to be reliable sources if they meet Wikipedia's guidelines for being reliable sources. They are valid in establishing notability if they provide in-depth, non-routine, non-trivial coverage of the subject.
Definition of a local interest
A subject is defined as a "local interest" if 100% of its sources are "local" sources.
Many urban areas have at least one newspaper, several television and radio stations with their own media, and often a lot more. Since they frequently duplicate each other's stories, it is likely that a lot of local interests have received coverage in more than one of these sources. This would seemingly meet the general notability guideline.
But not every run-of-the-mill subject can be notable.
In order for a local interest to be notable, it must, to a very high standard, have multiple reliable sources independent from the subject that provide in-depth, non-trivial coverage pertaining to the subject itself.