OpenHistoricalMap/Tags/Key/end_date

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OpenHistoricalMap logo.svg end_date
The Great Synagogue stood near this site until 1272.jpg
Description
Exact date when the feature went out of existence. Edit this description in the wiki page. Edit this description in the data item.
Group: lifecycle
Used on these elements
may be used on nodesmay be used on waysmay be used on areas (and multipolygon relations)may be used on relations
Useful combination
See also
Status: de facto

This key indicates when the feature went out of existence, for example when a settlement was abandoned, a building was demolished, a shop went out of business, or a tree was felled. It follows a basic format similar to ISO 8601-1.

You should always add end_date=* to every feature that no longer exists. Otherwise, data consumers handle a feature without an end date as if it currently exists (and will continue to exist for the foreseeable future).

How to map

Set end_date=* to the end date in YYYY, YYYY-MM, or YYYY-MM-DD format. Only include the day if you know the specific day, and only include the month if you know the specific month. For backwards compatibility, do not use other ISO 8601 syntaxes, such as week numbers or times of day. Instead, set end_date=* to the most accurate date you can express in the supported format, then use end_date:edtf=* to qualify the end date in the more flexible EDTF format (which also supports seasons, approximation, and uncertainty).

In ISO 8601, dates are calculated according to the proleptic Gregorian calendar. If your source indicates the end date in a calendar other than the Gregorian calendar, such as the Julian calendar, convert it to Gregorian before entering it into OpenHistoricalMap. If there the conversion is unintuitive or unambiguous, add an end_date:note=* tag explaining the conversion you performed. The proleptic Gregorian calendar records the year 1 BCE as 0000, 2 BCE as -0001, and so on.

More specifically, the end date is the date from which the feature and all its tags are no longer accurate. You can create another copy of the feature to represent its later stages and join them together using a chronology relation.

To indicate that a feature is still extant but is expected to go away at a particular time in the future, set its end_date=* to a date in the future. Use end_date:edtf=* in case of any uncertainty, but do not speculate on your own.

Examples

Software support

The OpenHistoricalMap website has a time slider that dynamically filters features on the map based on start_date=* and end_date=*. It supports values from -4000-01-01 (January 1, 4001 BCE) through December 31 of the current year.

The iD editor has an End Date field that sets end_date=*; it appears for every selected feature, regardless of its feature type. A validation rule automatically checks whether the value is well-formed and also whether any features overlap both spatially and temporally. A date filter shows and hides features based on start_date=* and end_date=* for convenience. Each feature's label includes its start_date=* and end_date=*; these labels appear on the map, in relation dropdown lists, validator warning messages, and in the Save panel's list of changes. [1]

See also