openapi: 3.0.3
info:
  title: Walk Score Cities API
  description: The Walk Score API returns Walk Score, Transit Score, and Bike Score for any location in the United States and Canada. Walk Score measures the walkability of any address on a scale from 0-100. Transit Score measures access to public transit and Bike Score measures bikeability. The API is used by real estate platforms, urban planning tools, commute calculators, and location intelligence applications.
  version: 1.0.0
  contact:
    url: https://www.walkscore.com/professional/api.php
  termsOfService: https://www.walkscore.com/professional/terms.php
servers:
- url: https://api.walkscore.com
  description: Walk Score API
security:
- apiKey: []
tags:
- name: Cities
  description: Supported cities list
paths:
  /transit/supported/cities/:
    get:
      operationId: listSupportedCities
      summary: List Supported Cities
      description: Returns a list of all cities supported by the Transit Score API, including city name, state (US) or country code (non-US), and estimated population. Use this to validate city/state combinations before requesting transit scores.
      tags:
      - Cities
      parameters:
      - name: wsapikey
        in: query
        required: true
        schema:
          type: string
        description: Your Walk Score API key
      responses:
        '200':
          description: Array of supported cities
          content:
            application/json:
              schema:
                type: array
                items:
                  $ref: '#/components/schemas/SupportedCity'
        '400':
          description: Invalid API key
components:
  schemas:
    SupportedCity:
      type: object
      properties:
        city:
          type: string
          description: Canonical city name
          example: Seattle
        state:
          type: string
          description: Two-letter US state code (US cities only)
          example: WA
        country:
          type: string
          description: Two-letter ISO-3166 country code (non-US cities only)
        population:
          type: integer
          description: Estimated city population
          example: 737000
  securitySchemes:
    apiKey:
      type: apiKey
      in: query
      name: wsapikey
      description: Walk Score API key, contact Walk Score to obtain