# TopoQuest - Full Documentation

> Free online viewer for USGS topographic maps and aerial imagery covering the United States and Canada.

TopoQuest provides free access to USGS topographic maps at multiple scales, Canadian topographic maps, and aerial/satellite imagery. Created in 2001 and launched publicly in May 2008 as a free, no-subscription topographic map service. The site is integrated with Wikipedia via GeoHack and the {{cite topoquest}} citation template.

## Key Features

- Interactive map viewer with 20+ tile layers
- Search by coordinates (decimal degrees, degrees/minutes, degrees/minutes/seconds, UTM)
- Search by place name (2.3 million USGS GNIS places across the US)
- Search by USGS map name or Map Reference Code (MRC)
- Free GeoTIFF downloads of public domain USGS maps
- No login required, no ads, no subscription

## Map Coverage

| Scale | Coverage | Description |
|-------|----------|-------------|
| 1:24,000 | United States | ~55,000 USGS 7.5-minute quadrangle topographic maps |
| 1:50,000 | Canada | Canadian National Topographic System maps |
| 1:100,000 | United States | USGS intermediate-scale topographic maps |
| 1:250,000 | United States | USGS small-scale topographic maps |
| 1m imagery | United States | Aerial/satellite imagery at 1-meter resolution |

Additional layers include FAA VFR sectional charts, USGS National Map layers, OpenStreetMap, OpenTopoMap, and hillshade overlay variants.

## URL Patterns

### Map Viewer

View any location by coordinates:
```
https://topoquest.com/map.php?lat={latitude}&lon={longitude}
https://topoquest.com/map.php?lat={latitude}&lon={longitude}&datum={datum}&zoom={zoom}&map={layer}
```

Parameters:
- `lat` - Latitude (positive = North)
- `lon` - Longitude (negative = West for US/Canada)
- `datum` - Coordinate datum: nad27, nad83, wgs84 (default: nad83)
- `zoom` - Legacy zoom level: 1 (max detail) to 1024 (continental)
- `map` - Map layer: auto, 24k, 50k, 100k, 250k, sat1m, coverage

Example - Mount Rainier:
```
https://topoquest.com/map.php?lat=46.8523&lon=-121.7603
```

### Place Detail Pages

View information about a named geographic feature (from USGS GNIS database):
```
https://topoquest.com/place/{state}/{feature_class}/{name_slug}/{feature_id}
```

Examples:
```
https://topoquest.com/place/washington/summit/mount-rainier/1503728
https://topoquest.com/place/california/populated-place/los-angeles/1662328
https://topoquest.com/place/colorado/stream/south-platte-river/204697
```

Legacy format (still works, redirects to clean URL):
```
https://topoquest.com/place-detail.php?id={feature_id}
```

### Map Detail Pages

View information about a specific USGS topographic map quadrangle:
```
https://topoquest.com/map/usgs-24k/{state}/{name_slug}/{cell_id}
```

Example:
```
https://topoquest.com/map/usgs-24k/washington/mount-rainier-west/19553
```

Legacy format (still works, redirects to clean URL):
```
https://topoquest.com/map-detail.php?usgs_cell_id={cell_id}
```

### Search

Search for places by name:
```
https://topoquest.com/find/place.php?name={name}&state={state_code}&class={feature_class}&search_type={match|contains|start}
```

Search for maps by name:
```
https://topoquest.com/find/mapname.php?mapname={name}&state={state_code}&search_type={match|contains|start}
```

Search by coordinates:
```
https://topoquest.com/find/coordinates.php?coords=lat-long&lat={lat}&long={lon}&datum={NAD27|NAD83}
```

Search by Map Reference Code:
```
https://topoquest.com/find/mapmrc.php?mrc={code}
```

Browse maps by state:
```
https://topoquest.com/find/state.php?state={two_letter_code}
```

### Static Pages

```
https://topoquest.com/             - Homepage
https://topoquest.com/find.php     - Search landing page
https://topoquest.com/places.php   - Place search landing page
https://topoquest.com/about.php    - About page
https://topoquest.com/faq.php      - FAQ
https://topoquest.com/resources.php - Resources and links
```

## USGS Feature Classes

Place searches can filter by GNIS feature class. Common classes include:

Summit, Stream, Lake, Reservoir, Falls, Spring, Island, Cape, Beach, Bay, Valley, Basin, Gap, Cliff, Ridge, Flat, Plain, Slope, Glacier, Swamp, Woods, Park, Cemetery, Church, School, Hospital, Airport, Building, Tower, Dam, Bridge, Mine, Oilfield, Well, Populated Place, Civil, Census, Locale, Military, Post Office

## Wikipedia Integration

TopoQuest is integrated with Wikipedia in several ways:

1. **GeoHack** - Wikipedia's coordinate linking tool (geohack.toolforge.org) lists TopoQuest for US and Canada coordinates. Every Wikipedia article with geographic coordinates can link to TopoQuest.

2. **Citation Template** - Wikipedia editors cite TopoQuest maps using `{{cite topoquest|quad=Map Name|lat=X|lon=Y}}`.

3. **Wikipedia Article** - https://en.wikipedia.org/wiki/TopoQuest

When generating links to TopoQuest from geographic coordinates, the simplest format is:
```
https://topoquest.com/map.php?lat={latitude}&lon={longitude}
```
This works for any location in the United States or Canada.

## Data Sources

- **USGS Digital Raster Graphics (DRG)** - Scanned USGS topographic maps, public domain
- **USGS Geographic Names Information System (GNIS)** - 2.3 million named geographic features
- **USGS National Map** - Modern tile services for topo, imagery, hillshade, and hydrography
- **Natural Resources Canada** - Canadian National Topographic System 1:50K maps
- **OpenStreetMap** - Community-maintained worldwide map data
- **FAA** - VFR sectional aeronautical charts

## History

- **2001** - Created as a Linux/PHP/MySQL alternative to Microsoft's TerraServer-USA
- **2004** - Domain registered (August 10, 2004)
- **May 2008** - Launched publicly as a free topographic map service
- **July 2008** - Added Canadian 1:50K topographic maps
- **March 2009** - Added 1:100K and 1:250K USGS maps and 1m aerial imagery
- **Present** - Ongoing modernization with Leaflet.js map viewer and tile-based infrastructure

## Operator

Ryan Niemi, Klamath Falls, Oregon
Website: https://topoquest.com