Real City Sounds can help you sleep by playing you a variety of soundscapes recorded around the United Kingdom.
This skill currently has real recordings of:
London's Trafalgar Square. The waves breaking on Brighton Beach. The wind blowing across the River Mersey in Liverpool. The calm around York Minster. Edinburgh's famous Royal Mile. The shoppers in Glasgow City Centre.
These are all real recordings, rather than stock audio.
You can skip to the next city by saying 'Alexa, skip'. And you can ask for a random city by saying 'Alexa, ask Real City Sounds to send me to sleep'.