Vetřelci v Coloradu (2002)

Three friends, Péťa, Ríša, and Ivana, decide to secretly follow Richard's older brother Radek and his friend Tomáš on their adventurous trip to Colorado. They believe it is a mythical place where aliens are hidden, unaware that it is actually a picturesque hill in the Czech countryside. They look forward to experiencing an exciting adventure. And indeed, the journey of the little children and big "men" turns into a series of unexpected, funny, and exciting events and dangerous situations, in which, surprisingly, the "little ones" will save the "big ones."