What this map shows
Every ~0.7 km2 hex (H3 resolution 8) in Greater Yerevan (Yerevan administrative city plus Abovyan and Ejmiatsin) is scored 0–100 on each of seven urbanism lenses, then combined into a single composite location-value score. All inputs come from openly licensed datasets so the index is fully reproducible.
Lenses
- 15-minute city — Number of distinct daily-life amenity categories reachable within ~15 min walk.
default weight 22% - Walkability — Street-network intersection density combined with nearby amenity count.
default weight 17% - Transit access — Public transport stops within walking distance, weighted by route count.
default weight 17% - Street centrality — Simplified street-network centrality (movement potential).
default weight 11% - Green & blue — Share of nearby area covered by parks, forest, grass, or water.
default weight 11% - Quiet & clean — Freedom from motorway noise and industrial neighbours (raw nuisance is inverted so higher = better).
default weight 11% - Topography & views — Elevation prospect and gentle-slope preference.
default weight 11%
Data sources
| Source | Used for | Licence |
|---|---|---|
| OpenStreetMap (Overpass) | amenities, road network, transit stops, parks, water, industrial land | ODbL |
| Yerevan community GTFS | transit frequencies (iteration 2) | open |
| Copernicus GLO-30 DEM | elevation, slope (iteration 2) | Copernicus open |
| Sentinel-2 (optional) | NDVI greenness (iteration 2) | Copernicus open |
Formulas
- 15-minute city: number of distinct daily-life amenity categories (food, school, health, retail, leisure, services, civic, transport) reachable within ~1.2 km euclidean of the hex centroid. Iteration 2 replaces this with a Valhalla pedestrian isochrone (15 min contour).
- Walkability: intersection density (degree ≥ 3) within 500 m + amenity count within 800 m.
- Transit: stops within 400 m, weighted by mode (metro > tram > bus). Iteration 2 adds GTFS-aware Valhalla multimodal reach.
- Street centrality (syntax): weighted sum of street-segment midpoints within 500 m (primary 5 · secondary 3 · tertiary 2 · residential 1). Simplified proxy for Hillier-style movement potential.
- Green: area-weighted count of parks, forest, grass, and water features within 600 m.
- Quiet & clean (inverse disamenities): raw penalty for proximity (< 150 m) to motorway/trunk/primary roads and for industrial land within 500 m. The raw value is inverted before storage so, like every other lens, a higher displayed score means a more desirable location.
- Topography: neutral 50 in the MVP. Iteration 2 will use Copernicus GLO-30 to score elevation prospect, slope gentleness, and openness.
All raw values are normalised by min/max with a 97th-percentile upper cap to keep a few outliers from flattening the colour ramp. The composite is a weighted mean of the visible, enabled lenses.
Limitations
- OpenStreetMap completeness varies. Coverage is solid for central Yerevan and weaker on the urban fringe.
- The MVP uses euclidean buffers, not network isochrones. Valhalla-backed isochrones land in iteration 2.
- Topography and NDVI are placeholders until the DEM and Sentinel-2 pipelines are wired in.
- This is a location index, not a price prediction. Calibration against listing data will be added when that data is available.