Nov 7, 2026Visualization

Lines of Access

See where federal records mark a legal way across private land to public land.

How to use this project

Help

How to explore

Public land can be hard to reach when private land lies between it and the road. The Bureau of Land Management records legal lines that let the public cross private land to reach federal land.

Start with the full map
See every line in the pinned layer, then choose a legal use, field office, or seasonal status to narrow the map.
Compare legal uses
Read each bar as a share of records, not a share of land or travel distance.
Check mapped length
Choose a length band and open one of the longest lines that remains in the filtered set.
Read one record
Use the public fields as a description of a legal right, not a promise that a road or gate is open today.

Access line: A line in this BLM layer where the federal government records a legal interest that provides public access across private land to federal land.
Easement: A legal right to use part of land owned by someone else for a stated purpose, such as reaching public land.
Legal use: The kind of use named in the source record: road, trail, recreation site, or a use defined in its legal document.
Mapped line length: The distance calculated along the coordinates stored for one line; it is not a complete walking or driving route.
Field office: The Bureau of Land Management office named in the source record; its count does not measure the amount of land it manages.
Seasonal status: Whether the layer records a seasonal restriction, records none, or leaves the field unstated.

Side Quest · November 7, 2026

Lines of
Access

See where federal records mark a legal way across private land to public land.

A public parcel can be hard to reach when private land lies between it and the road. The Bureau of Land Management records 4,832 public access lines where the federal government holds or reserves a legal interest.

Map the records

Start with every recorded line.

Each mark follows a line in the BLM layer. Change a control to see where that kind of record appears; the map does not show every public road, trail, or entrance.

Legal use

BLM field officeSeasonal status

4,832records shown

all legal uses, all field offices, all seasonal statuses, and all mapped lengths.

Compare uses

Most recorded access is a road.

The legal-use field names what the recorded right allows. The bar length is the share of all 4,832 records, not the share of land or travel distance.

Choose a bar to apply that legal use to the map and the length list.

Where records cluster

Compare the twelve field offices with the most lines.

These are record counts by the BLM office named in the layer. They do not measure how much public land an office manages.

Check length

Most mapped lines are short.

Length is calculated from each line's coordinates so every record uses the same measure. Choose a band to limit the map and the record list.

Longest in this selection

Open one record.

The list changes with every map filter. Selecting a row opens the source fields kept for that line.

Read one record

Pacific Crest Trail

This card keeps the public descriptive fields used in the project. It omits case numbers, serial numbers, project IDs, links, photos, and notes.

Legal use: Trail
Mapped line length: 0.81 mi
County field: San Bernardino
BLM field office: Palm Springs/S Coast Field Office
Property interest: Access Easement
Seasonal status: No seasonal restriction recorded
Recorded width: 30 ft
Source length field: 0.81 mi

How to read this

A legal record is not an open-gate report.

The layer records a federal property interest that provides public access. It does not confirm today's road condition, signs, gates, weather, fire closures, construction, or whether travel beyond this line is allowed.

Check current BLM maps and local notices before a trip.

Seasonal field

Most records say no seasonal restriction is recorded.

That field describes this dataset. It does not promise year-round physical access.

4,741No seasonal restriction recorded

17A seasonal condition is recorded

74Seasonal status is not stated

Read the data notes and limits

What this layer covers

The Bureau of Land Management describes these lines as federal interests in private land that provide legal public recreational or administrative access to federal land. Every record in this pinned layer is marked Public and releasable. This project does not treat the layer as a full inventory of entrances, public roads, or trails.

Why the length chart uses geometry

The source gives a positive length and unit for 4,021 of 4,832 records. Only 2,154 are within 20% of a length calculated from the mapped line. To compare every record consistently, the chart sums the coordinate-to-coordinate distance along each line. It does not add those values into a network total.

What is missing

Property-interest type is marked Unknown for 2,844 records. Seasonal status is unstated for 74. A missing field stays missing; it is never treated as none.

Static source

The browser uses a checked-in snapshot reduced from 7,042,500 source bytes retrieved on November 7, 2026. It makes no request to Data.gov, BLM, or ArcGIS.

Why this exists

The question

A coordinated map, legal-use comparison, office ranking, and consistent line-length measure can show what the BLM access layer contains without presenting it as a complete route map or a report of current physical access.

What to try

Start with all 4,832 recorded public access lines, filter them by legal use, field office, seasonal status, and mapped length, then open one record to read its public descriptive fields and limits.

Method and limits

About the data

I found the BLM National Public Lands Access Data Line in the allowlisted Data.gov catalog, then opened the underlying Bureau of Land Management ArcGIS item and feature service. Data.gov identifies the Bureau of Land Management as the publisher, marks the dataset public, and labels it U.S. public-domain work. The layer describes federal interests in private land that provide legal public recreational or administrative access to federal land. It is not a complete inventory of public roads, trails, entrances, or current on-the-ground conditions.

The source is pinned to the ArcGIS layer state retrieved November 7, 2026. The 98,027-byte layer schema has SHA-256 `d23aab54578bfb570770a62cc663679fed357e2b55931156be11acbfab8e33fd`. Three ordered GeoJSON queries at offsets 0, 2,000, and 4,000 contain 2,990,239, 2,658,365, and 1,295,869 bytes with SHA-256 values `ffedbe78b57a7de700d4b0c9fe3f184a8276b3ce75c234de30c6d8b3d6021ace`, `7dfda2956e501e001fdd678102c1034745e73f670d60f764b1cd99bedca2190c`, and `544f154dfbf5d40fbd8d524ef549850bdaf921ca4f3d29910d6d0de5e3b5cd89`. The queries request only public descriptive fields and five-decimal line geometry. They omit case-file numbers, serial numbers, local project IDs, URLs, photos, notes, and seasonal-detail text.

The reducer verifies the layer identity, edit timestamp, schema, page sizes, ascending unique object IDs, exact 4,832-record total, legal-use counts, and that every record is marked Public and releasable. It decodes field-office and property-interest values from the source domains, expands common abbreviations for display, groups seasonal status without turning a blank into none, and simplifies each line with a 0.0025-degree tolerance while preserving endpoints. Repeated reductions produced the same 741,182-byte browser snapshot at SHA-256 `e212d9b54efab16661fff6e6686449ba9c2aaef2ab3b3c95d872bff601cf456a`. The browser makes no request to Data.gov, BLM, or ArcGIS.

Mapped length is calculated before simplification by summing great-circle distance between every consecutive source coordinate. I use that common measure because only 4,021 records contain a positive length with a recognized unit, and 2,154 of those values are within 20% of the mapped line length. The interface keeps the source length beside an opened record but does not total it or silently substitute it for missing values. A mapped line may represent only a legal crossing segment, not a full route.

Counts describe records, not acres, ownership, visitation, traffic, route quality, or access demand. A record with no seasonal restriction does not establish that a road, trail, or gate is physically open all year. Fire, weather, construction, signs, closures, local rules, surface conditions, and permitted travel beyond the recorded line remain outside this dataset. Visitors should check current BLM maps and local notices before traveling.

Skills used

Data analysis
Data engineering
Statistical reasoning
Systems design
Visualization
Information design
Interaction design
Visual design
Creative coding
Product thinking
Editorial storytelling
Accessibility
Performance

What the data shows

The pinned layer contains 4,832 public, releasable access-line records. Roads account for 4,764, or 98.6%; the remaining records are 52 trails, 13 legally defined uses, and three recreation sites.
A consistent measurement along the source geometry puts 4,030 lines, or 83.4%, below one mile. Another 768 are from one to under five miles, and 34 are from five to under 20 miles.
The seasonal field records no restriction for 4,741 lines, a condition for 17, and no stated status for 74. No recorded restriction is a data value, not proof of year-round physical access.
The Medford Grants Pass Field Office has the most records in the layer at 384, followed by Roseburg Swiftwater at 333 and Roseburg South River at 269. These are record counts, not measures of managed land or access quality.

Sources

Bureau of Land Management via Data.gov · U.S. Public DomainBLM National Public Lands Access Data Line ↗Bureau of Land Management · U.S. Public DomainBLM National Public Lands Access Data Line — ArcGIS Hub item ↗Bureau of Land Management · U.S. Public DomainBLM National Public Lands Access Data Line — ArcGIS feature service ↗