About GIS

Everything is related to everything else, but near things are more related than distant things.

First Law of Geography - Waldo Tobler

A geographic information system (GIS) is a conceptualized framework that provides the ability to capture and analyze spatial and geographic data.

GIS provides the capability to relate previously unrelated information, through the use of location as the "key index variable". Locations and extents that are found in the Earth's spacetime, are able to be recorded through the date and time of occurrence, along with x, y, and z coordinates; representing, longitude (x), latitude (y), and elevation (z). All Earth-based, spatial–temporal, location and extent references, should be relatable to one another, and ultimately, to a "real" physical location or extent. This key characteristic of GIS, has begun to open new avenues of scientific inquiry and studies.


COHGIS stands for City of Houston Geographic Information System. COHGIS dataset is a common GIS dataset published by various departments or business units at the City of Houston.

COHGIS data is prepared and made available for general reference purposes only and should not be used, or relied upon for specific applications, without independent verification. The City of Houston neither represents, nor warrants COHGIS data accuracy, or completeness, nor will the City of Houston accept liability of any kind in conjunction with its use. COHGIS information is in the public domain and may be copied without permission; citation of the source is appreciated.

GIS @ Houston

MYCITY Houston

MYCITY Houston is the City of Houston public GIS webiste.

MYCITY websites and apps have been produced by the City of Houston as a public service for the sole purpose of geographic reference. No warranty is made by the City of Houston regarding specific accuracy or completeness.


Free and open access to the City of Houston's GIS data

MYCITY Internal GIS Portal

For city employee only


Houston Public Works Geographic Information Management System