Easy-to-read books, illustrated in full color with a horse charm! Five very special ponies live at Zonnehoeve: tough Jacco, beautiful Goldy, mischievous Romario, playful Rakki, and sensible Assa. Despite their antics, Carolien loves them all! Assa the Icelandic pony is thrilled when she hears Carolien's plan: they're going on a trek! That's just the thing for Assa. She loves trail rides and is never afraid of anything strange. During the trek, the ponies experience all sorts of exciting adventures. They have to cross a river by ferry, see wild boar, and Assa even participates in a race. But then, one night, the ponies are taken by horse thieves. Will they never see Zonnehoeve again? Assa has to do something! But what can one pony do, even her bravest?