Reading Elyne Mitchell's Silver Brumby series coloured my view of Australia as a child. My view's expanded a bit now to include some of the more minor geographical elements, like Sydney, and Melbourne, and Uluru, but if you'd asked me as child what was in Australia I'd have said mountains, and snowy ones at that. Not all the Silver Brumby stories take place in snow by any means, but those are the bits that I remember best: the Brumbies galloping lightly over the snow; ghost horses disappearing into the mist, and foolish Lightning getting himself and his mares trapped in the snow. I think my snow-bound view of the Brumbies was helped by the marvellous cover illustrations Peter Archer did for the later Dragon printing of Silver Brumby's Daughter, which is today's Advent calendar pony book.
You can read more about Elyne Mitchell here, and see some of the many Brumby printings.
Read more about the pony book in Heroines on Horseback, my survey of the world of the pony book from the 1930s onwards. You can buy a signed copy from me (I'll post them worldwide). The book's also available from the usual sources, or your local bookshop.