Dutch Portolan Demo

Name: Dutch Portolan Demo
Creator: Chris Holmes

A collection of datasets from various Dutch institutions to demonstrate a Spatial Data Infrastructure built on Portolan.

Product Details

Visibility: Public
Owner: Chris Holmes
Created: 6 May 2026
Last Updated: 6 May 2026

Product Contents

root

tudelft

3dbag

Product Details

Product Contents

Dutch Portolan Demo

A collection of datasets from various Dutch institutions to demonstrate a Spatial Data Infrastructure built on Portolan.

Product Details

Visibility: Public
Owner: Chris Holmes
Created: 6 May 2026
Last Updated: 6 May 2026

Product Contents

root

tudelft

3dbag

README

3D BAG

All ~10.8 million buildings in the Netherlands as 3D models, produced by the 3D Geoinformation Research Group at TU Delft in collaboration with 3DGI.

The 3D BAG enriches the official BAG building registry — maintained by Kadaster — with building heights, roof types, volumes, and surface areas derived from the AHN (Actueel Hoogtebestand Nederland) national point cloud survey. The source BAG footprints and attributes are available in this catalog as Buildings (Panden).

AI/Agent users: See llms.txt for field descriptions, query examples, and usage tips.

Data Sources

Source	Provider	What it contributes
BAG	Kadaster	Building footprints, construction year, status, usage function, floor area
AHN	Het Waterschapshuis	LiDAR point cloud (AHN3/AHN4/AHN5) for height derivation

The 3D BAG reconstruction pipeline automatically combines these two open datasets, using the AHN point cloud to compute building heights, roof geometry, volumes, and surface areas for every BAG building footprint. Models are validated with val3dity.

Spatial Coverage

Bounding Box: [3.36, 50.75, 7.23, 53.50] (all of the Netherlands)

Files

This collection contains three files derived from the 3D BAG:

3dbag-lod13.pmtiles (1.2 GB)

Vector tiles for web map visualization. Contains LOD 1.3 building-part polygons (14.1M features) with pre-computed height and base_height fields ready for MapLibre GL fill-extrusion rendering. EPSG:4326, zoom levels 0-15.

3dbag-lod13.parquet (747 MB)

GeoParquet for analytical queries. Same LOD 1.3 building-part data as the PMTiles in the original Dutch coordinate system (EPSG:7415 — Amersfoort / RD New + NAP height). 14.1M rows. Use for spatial joins, bulk analysis, and processing.

3dbag-pand.parquet (1.3 GB)

Whole-building GeoParquet with full 3D attributes. One row per building (10.8M rows), 62 columns including volumes, surface areas, floor counts, roof types, and AHN quality metrics. EPSG:7415. Join to the LOD 1.3 parts on identificatie for combined analysis.

Schema — LOD 1.3 Building Parts

The LOD 1.3 files (PMTiles and GeoParquet) share this schema:

Field	Type	Meaning
`identificatie`	string	BAG building ID (16 chars). Links to Kadaster BAG. First 4 digits = municipality code.
`b3_pand_deel_id`	int64	Building-part ID within a building. Buildings are split where roof heights differ.
`b3_dd_id`	int64	Sub-part ID within a building part.
`height`	double	Building part height in meters (roof 70th percentile minus ground elevation). Use as `fill-extrusion-height`.
`base_height`	double	Base elevation relative to ground in meters. Use as `fill-extrusion-base` for stepped parts.
`dak_type`	string	Roof type: `horizontal`, `slanted`, `multiple horizontal`, or `unknown`.

Schema — Whole Buildings (3dbag-pand.parquet)

The whole-building file has 62 columns. Key fields beyond the LOD 1.3 schema:

Field	Type	Meaning
`b3_h_maaiveld`	double	Ground level elevation (m, NAP datum)
`b3_h_nok`	double	Ridge line height (m)
`b3_bouwlagen`	double	Estimated floor count
`b3_volume_lod12`	double	Building volume at LOD 1.2 (m³)
`b3_volume_lod13`	double	Building volume at LOD 1.3 (m³)
`b3_volume_lod22`	double	Building volume at LOD 2.2 (m³)
`b3_opp_grond`	double	Ground floor area (m²)
`b3_opp_dak_plat`	double	Flat roof area (m²)
`b3_opp_dak_schuin`	double	Sloped roof area (m²)
`b3_opp_buitenmuur`

See the full 3D BAG attribute documentation for all 62 fields.

How the Files Relate

3dbag-lod13.pmtiles and 3dbag-lod13.parquet contain the same data — building parts with BAG attributes and computed heights — in different formats (vector tiles vs. GeoParquet) and CRS (EPSG:4326 vs. EPSG:7415).
3dbag-pand.parquet is one level up: whole buildings (not parts) with the full set of 3D metrics. Join to the LOD 1.3 files on identificatie.
The height fields in the LOD 1.3 files are already computed relative to ground, ready for extrusion rendering. The raw absolute heights (NAP datum) are in 3dbag-pand.parquet.

Relationship to BAG (Kadaster)

The 3D BAG is derived from the BAG building registry maintained by Kadaster:

The BAG provides 2D building footprints, construction year, status, usage function, and floor area — but no building heights or floor counts.
The 3D BAG adds heights, roof types, volumes, and surface areas by combining BAG footprints with AHN point cloud data.
The identificatie field is the shared key that links 3D BAG records back to BAG buildings.

If you need only 2D footprints with BAG attributes (and no heights), use Buildings (Panden) — it is smaller and simpler.

Quick Start — 3D Map Visualization

Use the PMTiles with MapLibre GL JS for instant 3D building visualization:

Quick Start — DuckDB Analytics

Quick Start — Python

Visualization Styles

Six MapLibre GL styles are provided — five use 3D fill-extrusion:

Style	Description
Default	Light grey 3D extruded buildings
By Height	Blue-to-red color ramp by building height (3D)
By Age	Brown-to-yellow by construction year (3D)
By Function	Categorical colors by building use (3D)
By Roof Type	Categorical colors by roof type (3D)
Flat	2D flat fill for overview/performance

Attribution

Produced by the 3D Geoinformation Research Group, TU Delft, and 3DGI. Funded by the European Research Council.

License

CC BY 4.0 — attribution required to the 3D Geoinformation Research Group, TU Delft.

Contact

Chris Holmes cholmes@9eo.org

README

3D BAG

All ~10.8 million buildings in the Netherlands as 3D models, produced by the 3D Geoinformation Research Group at TU Delft in collaboration with 3DGI.

AI/Agent users: See llms.txt for field descriptions, query examples, and usage tips.

Data Sources

Source	Provider	What it contributes
BAG	Kadaster	Building footprints, construction year, status, usage function, floor area
AHN	Het Waterschapshuis	LiDAR point cloud (AHN3/AHN4/AHN5) for height derivation

Spatial Coverage

Bounding Box: [3.36, 50.75, 7.23, 53.50] (all of the Netherlands)

Files

This collection contains three files derived from the 3D BAG:

3dbag-lod13.pmtiles (1.2 GB)

3dbag-lod13.parquet (747 MB)

3dbag-pand.parquet (1.3 GB)

Schema — LOD 1.3 Building Parts

The LOD 1.3 files (PMTiles and GeoParquet) share this schema:

Field	Type	Meaning
`identificatie`	string	BAG building ID (16 chars). Links to Kadaster BAG. First 4 digits = municipality code.
`b3_pand_deel_id`	int64	Building-part ID within a building. Buildings are split where roof heights differ.
`b3_dd_id`	int64	Sub-part ID within a building part.
`height`	double	Building part height in meters (roof 70th percentile minus ground elevation). Use as `fill-extrusion-height`.
`base_height`	double	Base elevation relative to ground in meters. Use as `fill-extrusion-base` for stepped parts.
`dak_type`	string	Roof type: `horizontal`, `slanted`, `multiple horizontal`, or `unknown`.

Schema — Whole Buildings (3dbag-pand.parquet)

The whole-building file has 62 columns. Key fields beyond the LOD 1.3 schema:

Field	Type	Meaning
`b3_h_maaiveld`	double	Ground level elevation (m, NAP datum)
`b3_h_nok`	double	Ridge line height (m)
`b3_bouwlagen`	double	Estimated floor count
`b3_volume_lod12`	double	Building volume at LOD 1.2 (m³)
`b3_volume_lod13`	double	Building volume at LOD 1.3 (m³)
`b3_volume_lod22`	double	Building volume at LOD 2.2 (m³)
`b3_opp_grond`	double	Ground floor area (m²)
`b3_opp_dak_plat`	double	Flat roof area (m²)
`b3_opp_dak_schuin`	double	Sloped roof area (m²)
`b3_opp_buitenmuur`

See the full 3D BAG attribute documentation for all 62 fields.

How the Files Relate

3dbag-lod13.pmtiles and 3dbag-lod13.parquet contain the same data — building parts with BAG attributes and computed heights — in different formats (vector tiles vs. GeoParquet) and CRS (EPSG:4326 vs. EPSG:7415).
3dbag-pand.parquet is one level up: whole buildings (not parts) with the full set of 3D metrics. Join to the LOD 1.3 files on identificatie.
The height fields in the LOD 1.3 files are already computed relative to ground, ready for extrusion rendering. The raw absolute heights (NAP datum) are in 3dbag-pand.parquet.

Relationship to BAG (Kadaster)

The 3D BAG is derived from the BAG building registry maintained by Kadaster:

The BAG provides 2D building footprints, construction year, status, usage function, and floor area — but no building heights or floor counts.
The 3D BAG adds heights, roof types, volumes, and surface areas by combining BAG footprints with AHN point cloud data.
The identificatie field is the shared key that links 3D BAG records back to BAG buildings.

If you need only 2D footprints with BAG attributes (and no heights), use Buildings (Panden) — it is smaller and simpler.

Quick Start — 3D Map Visualization

Use the PMTiles with MapLibre GL JS for instant 3D building visualization:

Quick Start — DuckDB Analytics

Quick Start — Python

Visualization Styles

Six MapLibre GL styles are provided — five use 3D fill-extrusion:

Style	Description
Default	Light grey 3D extruded buildings
By Height	Blue-to-red color ramp by building height (3D)
By Age	Brown-to-yellow by construction year (3D)
By Function	Categorical colors by building use (3D)
By Roof Type	Categorical colors by roof type (3D)
Flat	2D flat fill for overview/performance

Attribution

Produced by the 3D Geoinformation Research Group, TU Delft, and 3DGI. Funded by the European Research Council.

License

CC BY 4.0 — attribution required to the 3D Geoinformation Research Group, TU Delft.

Contact

Chris Holmes cholmes@9eo.org

1INSTALL spatial; LOAD spatial;
2
3-- Query LOD 1.3 building parts
4SELECT identificatie, height, base_height, dak_type, bouwjaar, gebruiksdoel
5FROM read_parquet('https://data.source.coop/cholmes/portolan-nl/tudelft/3dbag/3dbag-lod13.parquet')
6WHERE height > 50
7ORDER BY height DESC
8LIMIT 20;
9
10-- Query whole-building attributes
11SELECT identificatie, b3_volume_lod13, b3_opp_grond, b3_bouwlagen, b3_dak_type
12FROM read_parquet('https://data.source.coop/cholmes/portolan-nl/tudelft/3dbag/3dbag-pand.parquet')
13WHERE b3_volume_lod13 > 10000
14ORDER BY b3_volume_lod13 DESC
15LIMIT 20;

1INSTALL spatial; LOAD spatial;
2
3-- Query LOD 1.3 building parts
4SELECT identificatie, height, base_height, dak_type, bouwjaar, gebruiksdoel
5FROM read_parquet('https://data.source.coop/cholmes/portolan-nl/tudelft/3dbag/3dbag-lod13.parquet')
6WHERE height > 50
7ORDER BY height DESC
8LIMIT 20;
9
10-- Query whole-building attributes
11SELECT identificatie, b3_volume_lod13, b3_opp_grond, b3_bouwlagen, b3_dak_type
12FROM read_parquet('https://data.source.coop/cholmes/portolan-nl/tudelft/3dbag/3dbag-pand.parquet')
13WHERE b3_volume_lod13 > 10000
14ORDER BY b3_volume_lod13 DESC
15LIMIT 20;

1import geopandas as gpd
2
3gdf = gpd.read_parquet(
4    'https://data.source.coop/cholmes/portolan-nl/tudelft/3dbag/3dbag-lod13.parquet',
5    columns=['identificatie', 'height', 'base_height', 'dak_type', 'bouwjaar', 'geom']
6)
7print(f"CRS: {gdf.crs}")  # EPSG:7415
8print(f"Rows: {len(gdf):,}")

1import geopandas as gpd
2
3gdf = gpd.read_parquet(
4    'https://data.source.coop/cholmes/portolan-nl/tudelft/3dbag/3dbag-lod13.parquet',
5    columns=['identificatie', 'height', 'base_height', 'dak_type', 'bouwjaar', 'geom']
6)
7print(f"CRS: {gdf.crs}")  # EPSG:7415
8print(f"Rows: {len(gdf):,}")

1map.addSource('3dbag', {
2  type: 'vector',
3  url: 'pmtiles://https://data.source.coop/cholmes/portolan-nl/tudelft/3dbag/3dbag-lod13.pmtiles'
4});
5
6map.addLayer({
7  id: 'buildings-3d',
8  type: 'fill-extrusion',
9  source: '3dbag',
10  'source-layer': 'buildings',
11  paint: {
12    'fill-extrusion-color': '#D4D4D4',
13    'fill-extrusion-height': ['get', 'height'],
14    'fill-extrusion-base': ['get', 'base_height'],
15    'fill-extrusion-opacity': 0.85
16  }
17});

1map.addSource('3dbag', {
2  type: 'vector',
3  url: 'pmtiles://https://data.source.coop/cholmes/portolan-nl/tudelft/3dbag/3dbag-lod13.pmtiles'
4});
5
6map.addLayer({
7  id: 'buildings-3d',
8  type: 'fill-extrusion',
9  source: '3dbag',
10  'source-layer': 'buildings',
11  paint: {
12    'fill-extrusion-color': '#D4D4D4',
13    'fill-extrusion-height': ['get', 'height'],
14    'fill-extrusion-base': ['get', 'base_height'],
15    'fill-extrusion-opacity': 0.85
16  }
17});

Dutch Portolan Demo

Dutch Portolan Demo

3D BAG

Data Sources

Spatial Coverage

Files

3dbag-lod13.pmtiles (1.2 GB)

3dbag-lod13.parquet (747 MB)

3dbag-pand.parquet (1.3 GB)

Schema — LOD 1.3 Building Parts

Schema — Whole Buildings (3dbag-pand.parquet)

How the Files Relate

Relationship to BAG (Kadaster)

Quick Start — 3D Map Visualization

Quick Start — DuckDB Analytics

Quick Start — Python

Visualization Styles

Attribution

License

Links

Contact

3D BAG

Data Sources

Spatial Coverage

Files

3dbag-lod13.pmtiles (1.2 GB)

3dbag-lod13.parquet (747 MB)

3dbag-pand.parquet (1.3 GB)

Schema — LOD 1.3 Building Parts

Schema — Whole Buildings (3dbag-pand.parquet)

How the Files Relate

Relationship to BAG (Kadaster)

Quick Start — 3D Map Visualization

Quick Start — DuckDB Analytics

Quick Start — Python

Visualization Styles

Attribution

License

Links

Contact