Blog · October 14, 2026 · California
Reading the Corte Madera Plat Map for a lot
A recorded plat shows how land near Tiburon was divided into lots.
Main page: Marin County, CA GIS & Parcel Viewer (official map link, county facts and neighboring maps).
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When a listing near Larkspur mentions a lot number, look up the Corte Madera plat map it refers to. What this Corte Madera guide covers: where plats are filed, plat versus tax map, and what to look for on the sheet.
Tracking down the Corte Madera plat map
For a parcel near Larkspur, recorded plats sit with the County Recorder, usually in a plat book or cabinet.
The free map to start with
Parcels around Mill Valley appear on the Marin County parcel viewer, free to use and open without a login. For a tract near Larkspur, enter a street address, an owner's name or a parcel number, then pick the result to center the map on it. If the land is near Ross, the record panel usually lists the owner of record, acreage on the tax roll, the parcel number and in many cases the last transfer.
When there's no plat
Acreage around Ross outside a subdivision may have no plat at all; the deed and any recorded survey describe it instead.
Neighboring parcel maps
Marin County borders Contra Costa County, San Francisco County, Solano County, and Sonoma County, all with their own assessor records. A tract near the line by Mill Valley can show up across two assessors' files, so look at the adjacent map too. For a home near Belvedere, the Platbookmapper state page lists each neighboring county map across California.
City limits and county records
Corte Madera is part of Marin County, California, and the county assessor maps its lots. For land near Belvedere, the municipality handles things like zoning, permits and utilities for lots inside the boundary, and the county still keeps the parcel and deed records. Lots just outside the city limits out by Belvedere generally follows county rules instead.
Which office to call
Anything recorded against property around Belvedere are with the County Recorder, usually searchable by name or document number. Building or septic questions for a lot near Belvedere go to planning, building or health offices, depending on whether the land is inside town limits.
Two different maps
Where lines don't match in Corte Madera, the recorded plat and a survey control.
A word on accuracy
Parcel lines are drawn for taxes, not surveyed, so the edge of a yard near San Rafael may sit a few yards off the line on screen. For a tract near Tiburon, owner names and values update on a schedule, so a deed recorded last month may not show yet.
The paper trail behind a parcel
The map is an index, not the title: recorded deeds, subdivision plats and easements for land near Mill Valley sit with the County Recorder. Closer to Larkspur, have ready the document number shown in the record panel to skip a name search.
On site with the map
The parcel map usually runs in a mobile browser, which helps when you're standing on land near Belvedere, but coverage can be spotty out of town. A screenshot of the parcel near Mill Valley with its ID is a good backup.
Replats and vacations
Lots near Tiburon can be combined or reconfigured by a replat, so check for later filings; street vacations near Mill Valley show up in the records too.
How land is described here
California uses the Public Land Survey System, so rural legal descriptions near Larkspur cite 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 Ross can be irregular. Write down the legal description for the tract near San Rafael when you talk to a surveyor.
What a plat shows
If the land is near San Rafael, the sheet usually includes lot and block numbers, dimensions and bearings, street rights-of-way and easements.
Places you'll see on the map
San Rafael holds the county offices, where most land records are kept. You'll also find Larkspur, Mill Valley, and Ross, each with its own cluster of lots. Around 254,407 people live in Marin County (Census estimate, 2023) on roughly 520 square miles. Places such as San Pablo Bay, San Francisco Bay, and Golden Gate National Recreation Area make handy reference points on the map near Larkspur.
Getting a copy
Closer to Belvedere, many recorder offices offer an online index, otherwise call or visit with the reference; small fees are common.
Corte Madera: common questions
Who has recorded plats for land near Tiburon?
Good question; recorded plats near Mill Valley are filed with the County Recorder; small copy fees are common.
Is the Corte Madera plat map the same as the county GIS?
Short answer: the plat near Larkspur is recorded, while the GIS layer is an approximation; a surveyor ties it to the ground.
Are old plats online in Corte Madera?
Good question; older plats near Belvedere may be on film or paper.
What is a replat near Belvedere?
Good question; lot splits in Corte Madera go through the planning office.
What is a parcel ID near Tiburon?
It's the number the County Assessor uses to track a tract near Belvedere; you'll see it in the viewer and on tax statements.
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.