The coverage of Google Street View is not universal so it may not always be available and you may dip in and out of it as you complete your virtual walk. There are some countries, like Austria, in which Google Street View does not operate.
If Google Street exists for the point you reach in a walk on World Walking you will see it. If it doesn't then you will see you will be presented by a gray screen.
You can find more information about this at: https://en.wikipedia.org/wiki/Google_Street_View_privacy_concerns
In addition, some of our virtual routes allow you to 'walk across water', for example, crossing the Atlantic Ocean as you journey from the UK to the USA. World Walking uses Google Maps which is unable to detect where you are while your are crossing the water as there are no reference points. In such instances your Google Street View will remain as the last one you saw before you headed off across the water. Providing Google Street View is operational at your destination on the other side you will pick it up again once you have reached dry land on the other side and the map of your walk is updated.
Here's a link to an article in our Help section (you can find the link to this at the bottom of each page on the website) which explains about the map not updating: https://worldwalking.org/help/article/6752/why-does-the-map-not-re-draw-update-straight-away.