Blog · October 14, 2026 · California
Larkspur Plat Map, California: plats and lots
Lots in Larkspur trace back to recorded plats filed with the county.
Main page: Marin County, CA GIS & Parcel Viewer (official map link, county facts and neighboring maps).
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If a legal description for land in Larkspur cites a lot number, you'll need the Larkspur plat map to make sense of it. In this Larkspur guide: where plats are filed, plat versus tax map, and what to look for on the sheet.
Getting started with the Larkspur plat map
For a subdivision near San Anselmo, the deed or parcel record often names the subdivision and plat reference; that makes the request quick.
The viewer Marin County publishes
Your first stop is the Marin County parcel viewer; it maps each assessed parcel in the county, Ross included. Without an address in hand, pan along US Route 101 until the lines appear, then click inside the one you want. For property near Tiburon, write down the parcel ID while you have it open; each records desk in the county uses it to find the file.
How land is described here
California is laid out under the Public Land Survey System, which means a tract near San Rafael is described by section, township and range. A standard section is about one square mile, roughly 640 acres, and a township holds 36 of them, though sections near Mill Valley can be irregular. Keep the legal description for land near Ross for any title or survey request.
Next door to Marin County
Marin County meets Contra Costa County, San Francisco County, Solano County, and Sonoma County; every one of them runs a separate parcel map. Ground near Ross that runs to the line may be split across two assessors' files, so open the adjacent map as well. On ground around Ross, our state page links every bordering county map across California.
Where Larkspur fits in
Larkspur is part of Marin County, California, which means parcel data comes from the county. Local government in Larkspur handles things like zoning, permits and utilities within town limits, and the county still keeps the parcel and deed records. Land beyond the town limits near San Rafael generally answers to county rules instead.
Metes and bounds instead
Acreage around San Anselmo outside a subdivision is often described by metes and bounds or survey description; the deed and any recorded survey describe it instead.
How a plat differs from the tax map
If the tax map and plat differ near San Anselmo, trust the recorded documents over the GIS layer.
Using it on a phone
The parcel map usually runs in a mobile browser, which helps when you're standing on land near Corte Madera, but coverage can be spotty out of town. A printout of the tract near Ross is a good backup.
Replats and vacations
Lots near Mill Valley can be combined or reconfigured by a replat, so check for later filings; street vacations near Ross show up in the records too.
Which office to call
Deeds, mortgages and recorded plats for land near Mill Valley are with the County Recorder, sometimes only in person. Zoning, permits and septic questions near Mill Valley need the planning or permitting office, town or county, depending on location.
Details on the Larkspur plat map
Easements on the plat near Ross limit where you can build or fence; read the notes on the sheet.
Places you'll see on the map
San Rafael holds the county offices, where most land records are kept. You'll also find Corte Madera, Mill Valley, and Ross, each with its own cluster of lots. Around 254,407 people call Marin County home (Census Bureau estimate, 2023) spread over roughly 520 square miles. Landmarks such as San Pablo Bay, San Francisco Bay, and Golden Gate National Recreation Area make handy reference points on the map near Tiburon.
Getting a copy
Closer to San Rafael, some counties put plat images online, while others require a visit or a request; small fees are common.
Before you lean on the lines
The acreage figure is an assessed number; only a licensed surveyor establishes the real lines for a parcel near Ross. If you're looking near San Rafael, owner names and values update on a schedule, so a deed recorded last month might lag behind.
Backing up the map with records
When the details count, get the recorded deed from the County Recorder; the parcel map near San Rafael only summarizes it. With a lot near San Rafael, have ready the document number listed on the parcel record so staff can find the deed fast.
Larkspur: common questions
What does lot 7, block 3 mean near Mill Valley?
Around Corte Madera, lot and block refer to a numbered lot within a block on a recorded subdivision plat.
How is a plat different from the parcel map near Corte Madera?
For acreage around San Rafael, a recorded plat is based on a survey, but the GIS map is not; a surveyor ties it to the ground.
Are old plats online in Larkspur?
Good question; older plats near Mill Valley may be on film or paper, including older subdivisions.
What do the dashed lines on a plat mean for land near Mill Valley?
If you're looking near Ross, dashed lines often mark easements or building lines, so check before you build.
How do I save a parcel from the viewer around San Anselmo?
Most viewers have a print or export tool; include the record panel for the lot near Tiburon.
Open the official Marin County, CA parcel map See it in the Platbookmapper directory
Not a survey. County GIS and tax parcel maps are assessment and planning layers. They are not a substitute for a recorded plat, deed, or licensed survey, especially for fences, setbacks, or boundary disputes.