# OpenStreetMap XYZ — central London

Load a small slippy-map window, compute it, and plot the mosaic.

Uses `XYZConfig.for_openstreetmap` (identifiable User-Agent, max 2 in-flight, ~2 req/s). Include **© OpenStreetMap contributors** when displaying the imagery.

```{note}
OSM raster tiles are often **palette PNGs**, so the mosaic may be single-band (grayscale) today. For a full-colour RGB XYZ example see {doc}`gibs-bluemarble`.
```

## Code

```python
from tilearray import XYZConfig, create_array
from tilearray.types import CRS, Format

config = XYZConfig.for_openstreetmap(
    zoom=16,
    output_format=Format.PNG,
    chunk_size=(256, 256),
)

bbox = (-0.005, 51.495, 0.005, 51.505)  # ~central London
da = create_array(config, bbox, CRS.EPSG_4326, compute=True)
print(da.shape, da.dims, da.attrs["service_type"])
```

## Result

```{image} ../_static/guides/osm-london.png
:alt: OpenStreetMap mosaic over a small central London bbox
:width: 480px
```

Map data © OpenStreetMap contributors.

Example shape for this window: about `(1024, 512)` (tile alignment can change that). Stay within OSMF tile policy — prefer the preset; do not raise concurrency past its caps.