This screenshot is of the ActiveWorlds Gateway world version 5.0, which went online on November the 26th 2009. Here we see a view across the laputa, or flying island that the world is styled as, to the far side of the island, where two more such laputa are flying in the sky behind this one.
The symbology is ideal for a platform such as ActiveWorlds, which is a collection of many hundreds of completely separate worldlets all under a single client. Each may be anything from 20 metres across to a max of 65 kilometres across. However, each is indeed an island, and passing the edge of any one, you can never reach any of the others, no matter how far you keep on walking.
In fact, this analogy holds up very well for all types of VR. Millions of individual worlds hanging in the ether, each completely separate from one another, lucky to even catch a distant glimpse.
Perhaps unintentionally, this view also serves as a simile for the constant attempts to define cross-platform standards for VR clients, such as it is possible to hop from one virtual laputa to another, irrespective of which differing platforms and capabilities each was created out of.
Link: World Review: ActiveWorlds Gate 5.0
Link: The Laputa and VR