Miscellaneous Information

Various Identification Codes ...

GNIS Codes ...

The U.S. Board on Geographic Names (BGN) was created to address the problems caused by spelling and naming variations. The BGN will usually recognize an existing name or, when necessary, establish a new name for a geographic feature (such as a mountain, lake, river, stream, city, town, village, dam, bridge, etc).

The BGN names are kept in a database called the Geographic Names Information System (GNIS) and it is the official Federal repository. The GNIS is operated and maintained by the U.S. Geological Survey (USGS).

A unique and permanent identifier has been assigned for each name in the GNIS database. These names and identifiers are definitive and it is intended that they are to be used by all departments of the Federal Government:

GNIS ID for Mill Valley: 2411109

GNIS ID for Marin County: 277285

GNIS ID for California: 1779778

FIPS Codes ...

In a past effort, various federal agencies created a set of codes with a purpose similar to the GNIS codes. These codes are called the Federal Information Processing Standard (or the FIPS 55 codes). Although they are still used by some organizations, the FIPS codes are obsolete and will ultimately be replaced by the GNIS codes.

The following FIPS codes apply to Mill Valley:

Place (Community) Code:	47710
State Code:	06 (California)
County Code:	041 (Marin County)

Since the Place and County FIPS codes are not unique and can be repeated in other States, it's necessary to combine the State code with the Place and County FIPS codes to uniquely identify them - for example:

State/Place Code:	06/47710
State/County Code:	06/041

As already mentioned, the FIPS codes are to be replaced by the GNIS codes. The following reflect those changes:

	FIPS Code	translates to	GNIS Code
State of California:	06		1779778
Marin County:	06/041		277285
Mill Valley:	06/47710		2411109

GPS Location - GNIS vs Census ...

An important aspect of the GNIS code is that it assigns a GPS location (the latitude/longitude) to the geographic feature. This location is simply a point on the map and does not represent the size or shape of the feature. In the case of Mill Valley, it is a point within Mill Valley that might be a post office, the city hall or simply an intersection - the point should really be considered arbitrary and only indicating a general location.

For Mill Valley, the GNIS GPS location is given as:

Lat:   37° 54' 29"   (or 37.91°)

Lon:   -122° 32' 30"   (or -122.54°)  

Determined by its statistical needs, the Census Bureau has defined a sampling area for Mill Valley - this area also contains a map point. As with the GNIS code, the location of the Census point should be considered as being arbitrary within the sampling area.

For Mill Valley, the Census 2010 GPS location is given as:

Lat:   37° 54' 30"   (or 37.91°)

Lon:   -122° 32' 31"   (or -122.54°)  

The map point defined by the Census Bureau lies 134.7 feet to the northwest<1> of the point given by the GNIS (see above).

You might note that the GPS location given for the 2010 Census is different than the location that was specified by the 2000 Census:

Lat:   37° 54' 19"   (or 37.91°)

Lon:   -122° 32' 35"   (or -122.54°)  

The GPS location given for the 2000 Census lies 1,095 feet to the south<2> of the point given by the 2010 Census.

Regional Codes ...

For statistical purposes, the US Census Bureau has divided the country into four Regions. Mill Valley is located in Region #4 (the West Region).

In turn, the US Census Bureau has further divided each Region into Divisions. Mill Valley is located in Division #9 (the Pacific Division).

The Office of Management and Budget (OMB) has created ten Federal Regions. Mill Valley is located in Region IX (Region 9).

The Federal Emergency Management Agency (FEMA) has created ten Management Regions. Mill Valley is located in Region IX (Region 9).

ZIP Codes ...

While some people have used a ZIP code to identify a community, the purpose of the ZIP code was to make mail delivery more efficient by grouping addresses together. Although the ZIP Code doesn't specifically identify a city like Mill Valley, it does identify addresses that are in (or near) Mill Valley. It's important to remember that the boundaries of a ZIP Code are defined by the needs of the USPS and can be changed, re-assigned or overlapped with other ZIP Codes.

The ZIP code for Mill Valley: 94941-94942<3>

Referenced GNIS Records ...

GNIS ID #1659128   (Name of Record: Mill Valley)

Class: populated place

A place or area having clustered or scattered buildings and a permanent population (such as a city, settlement, town or village). The boundaries may or may not coincide with the perceived population.

A 'populated place' record may have a corresponding 'census' or 'civil' record. The information contained in the 'populated place' record applies only to the class and should not be confused with either the 'census' and 'civil' classes.

County: Marin

Map Name: San Francisco and Vicinity

Lat: 37.9060368       Lon: -122.5449763  

Elev: 24 ft.

GNIS ID #2411109   (Name of Record: City of Mill Valley)

Class: civil

A political division formed for administrative purposes (such as a borough, county, incorporated place, parish, town or township).

A 'civil' record may have a corresponding 'census' or 'populated place' record. The information contained in the 'civil' record applies only to the class and should not be confused with either the 'census' and 'populated place' classes.

County: Marin

Map Name: San Francisco and Vicinity

Lat: 37.9081154       Lon: -122.54175  

Elev: 41 ft.

Referenced FIPS Records ...

FIPS Code: 06/47710   (Place Name: Mill Valley)

County: Marin     (FIPS State/County: 06/041)

Class: C1

Identifies an incorporated place (ie- Mill Valley) that does not serve as a primary county division - or in other words, it is included in and is part of a primary county division (ie- Marin County).

GSA Code: 2180

MRF Code: 1765

MSA Code: 7360

Off-the-Road Links ...

The official website for Mill Valley: www.cityofmillvalley.org/

The official website for Marin County: www.co.marin.ca.us/

The official website for State of California: https://www.ca.gov/

The official website of the U.S. Board on Geographic Names (BGN)

The official website of the U.S. Geological Survey (USGS)

The official website of the U.S. Census Bureau

The official website of the U.S. Office of Management and Budget (OMB)

The official website of the U.S. Federal Emergency Management Agency (FEMA)