Nicasio, California
23 topographic sheets cover this place, the earliest surveyed in 1914 and the latest in 1983. It stands in the Northwest Marin census division. It lies in ZIP code area 94946. It lies near Lucas Valley. The Survey maps it on the San Geronimo quadrangle. 81 people lived here at the 2020 count. It stands 194 feet above sea level.
Then and now
1914 to 1983The same ground, surveyed 69 years apart. Drag the handle to wipe between them. Both sheets are United States Geological Survey originals; neither has been altered.


Population over time
2 figuresNicasio fell from 96 to 81 between 2010 and 2020. These are the recorded population figures Wikidata holds for this place, reached through the Geographic Names Information System number this page is keyed on rather than by name, so they belong to this place and not to another of the same name. Most are census counts, but not all are: an early figure may be a founding or settlement estimate, and an estimate published within five years of a census is left out. The change column is computed, and is left blank where more than 20 years separate a figure from the one before it, because a gap that long is not a change between two counts.
| Year | People | Change |
|---|---|---|
| 2010 | 96 | |
| 2020 | 81 | -15 (-16%) |
Topographic sheets covering this place
10 surveys from 23 printed sheetsMatched by testing this settlement's coordinate against the published boundary of every sheet in the United States Geological Survey's historical collection. Each opens the scanned sheet at the Survey.
- 1914 USGS Petaluma quadrangle1:62500, 5 printings
- 1942 USGS Petaluma quadrangle1:62500
- 1947 USGS Santa Rosa quadrangle1:250000
- 1949 USGS Santa Rosa quadrangle1:250000, 2 printings
- 1954 USGS Petaluma quadrangle1:62500, 3 printings
- 1954 USGS San Geronimo quadrangle1:24000, 5 printings
- 1958 USGS Santa Rosa quadrangle1:250000, 3 printings
- 1962 USGS Santa Rosa quadrangle1:250000
- 1964 USGS Santa Rosa quadrangle1:250000
- 1983 USGS Napa quadrangle1:100000
Fires near this place
29 since 1992Regional context, not property-specific evidence. The federal wildfire occurrence database lists 29 fires within 5 miles of Nicasio between 1992 and 2020, burning about 258 acres in total. 1 started naturally. 1 was recorded as arson. Distance is straight-line from the map coordinates, so a fire counted here may appear on a neighbouring settlement's page as well.
| Reported cause | Fires |
|---|---|
| Missing data/not specified/undetermined | 8 |
| Equipment and vehicle use | 7 |
| Power generation/transmission/distribution | 6 |
| Fireworks | 2 |
| Recreation and ceremony | 2 |
| Misuse of fire by a minor | 1 |
| Debris and open burning | 1 |
| Natural | 1 |
| Arson/incendiarism | 1 |
The most recent of them, most recent first, with the day each was reported and the service that recorded it.
| Date | Cause | Size | Reported by | Name on the report |
|---|---|---|---|---|
| 21 September 2017 | Missing data/not specified/undetermined | 8.2 acres | Point Reyes National Seashore | DRAKE 2 |
| 10 September 2018 | Equipment and vehicle use | 151 acres | California Department of Forestry & Fire Protection | not named |
| 9 August 2012 | Misuse of fire by a minor | under an acre | Marin County Fire Department | not named |
| 9 August 1992 | Fireworks | 2.2 acres | Golden Gate National Recreation Area | OLEMA I |
| 9 August 1992 | Fireworks | 4.6 acres | Golden Gate National Recreation Area | OLEMA II |
| 28 August 2007 | Missing data/not specified/undetermined | 6.0 acres | Marin County Fire Department | not named |
| 27 August 2009 | Arson/incendiarism | under an acre | Marin County Fire Department | not named |
| 13 August 2009 | Equipment and vehicle use | 4.0 acres | Marin County Fire Department | not named |
Settlements close enough to share some of these fires:
Mines and quarries near this place
10 of 12 shownRegional context, not property-specific evidence. The federal mineral resources record lists 12 workings within 5 miles of Nicasio: 10 occurrences, 1 prospect, 1 producer. 1 still produces. What was taken out: Stone, Crushed/Broken, Gold, Mercury, Gemstone. Distance is straight-line from the map coordinates, so a quarry counted here may appear on a neighbouring settlement's page as well.
| Where | Site | Commodity | Status | Recorded |
|---|---|---|---|---|
| Black Mountain | Stone | Occurrence | ||
| Fort Baker | Manganese, Gold | Occurrence | Psilomelane | |
| Mount Tamalpais Cemetery Quarry. | Stone, Stone, Dimension, Stone, Crushed/Broken | Occurrence | ||
| Unnamed Location | Gemstone | Occurrence | ||
| Claims | Mercury | Occurrence | ||
| Claims | Mercury | Occurrence | ||
| Black Mountain | Stone, Crushed/Broken | Occurrence | ||
| Ft. Baker | Stone, Crushed/Broken | Occurrence | ||
| Inverness Ridge | Gold | Occurrence | ||
| Lafranchi Quarry | Stone, Crushed/Broken | Producer |
Storms near this place
1 since 2010Regional context, not property-specific evidence. The National Weather Service names Nicasio in 1 storm report in 2010: 1 flood. No death or injury is recorded in these reports. Each account below is quoted exactly as the forecast office filed it, from the NOAA Storm Events Database, and each date opens the federal record of that event.
| When | Event | Place named | Harm | What the report says |
|---|---|---|---|---|
| April 2010 | Flood | Nicasio | $12,000 | Heavy rain caused flooding at the intersection of Wilson Hill and Marshall Petaluma Roads. Mud consumed the westbound lane and a large tree fell onto the roadway. |
Nearest settlements
The eight closest, with where each one stands in the county. Distances are straight-line, computed from the Geographic Names Information System coordinates.
| Map | Place | Distance | Sheets |
|---|---|---|---|
| Jewell | 3.0 miles | 23 | |
| Taylorville (historical) | 3.2 miles | 23 | |
| Forest Knolls | 3.2 miles | 23 | |
| Tocaloma | 3.3 miles | 28 | |
| Irving (historical) | 3.4 miles | 23 | |
| Lagunitas | 3.5 miles | 23 | |
| San Geronimo | 3.8 miles | 23 | |
| Shafter | 4.0 miles | 23 |
Elsewhere
Matched on this settlement's Geographic Names Information System number rather than its name, so it cannot be a different place of the same name in another state.
| Wikipedia article on Nicasio | An encyclopaedic summary. Its text is share-alike, so it is linked here rather than copied. |
| Wikidata item Q3476052 | The structured record the population and elevation above come from. Public domain (CC0). |
Provenance
This settlement is recorded in the Geographic Names Information System as feature 1659226. The sheet list is computed by point-in-boundary test against the United States Geological Survey's historical topographic inventory. Both are works of the United States government and carry no copyright under 17 U.S.C. 105.
Wildfire. Short, Karen C. 2022. Spatial wildfire occurrence data for the United States, 1992-2020 [FPA_FOD_20221014]. 6th Edition. Fort Collins, CO: Forest Service Research Data Archive. https://doi.org/10.2737/RDS-2013-0009.6 Collected with United States Government funding and usable without additional permissions or fees.
Mines and quarries. USGS Mineral Resources Data System (MRDS) https://mrdata.usgs.gov/mrds/ A work of the United States government, no copyright under 17 U.S.C. 105.
Storms. NOAA National Centers for Environmental Information, Storm Events Database https://www.ncei.noaa.gov/stormevents/ A work of the United States government, no copyright under 17 U.S.C. 105. Narratives are quoted verbatim from the National Weather Service report and are not edited or summarised.









