JCDecaux's self-service bicycles.
JCDecaux Bike API is a free Sports & Fitness API that requires apiKey authentication, is served over HTTPS and has unconfirmed CORS support.
Details from developer.jcdecaux.com.

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Geocode an address, validate an email, track a flight or pull stock data with one account, one dashboard and one API key.
Display football standings e.g epl, la liga, serie a etc. The data is based on espn site
The JCDecaux Bike API is provided by JCDecaux Developer (developer.jcdecaux.com).
Yes. The JCDecaux Bike API is listed in the Sports & Fitness category of the public-apis directory, which only includes APIs that are free or have a free tier. Check its documentation for rate limits and paid plans.
Yes. The JCDecaux Bike API uses apiKey authentication, so you need to register for credentials before making requests.
CORS support for the JCDecaux Bike API is unknown. Test a request from the browser, and fall back to a server-side call if it is blocked.
Yes. The JCDecaux Bike API is served over HTTPS, so it's safe to use in production.