Play is a fundamental activity for experiences, learning and development among children in their early years. Early childhood education and care (ECEC) institutions' play environments, their features and design, are therefore of great importance for the opportunities provided for children to create and engage in a wide range of play. This study examines how children utilise features in the ECEC outdoor environment (spaces and materials) to engage in different types of play. Children (3-6 years, N = 86) were observed in two-minute sequences during periods of the day when they were free to choose what to do. The data consists of 935 randomly recorded two-minute videos, which were coded second by second to register the type of play occurring, the space in which it occurred and the materials children used. The results indicate a dynamic relationship between the outdoor environments and the play in which children engage and point out the complex nature of playground design, where planning for the predictable, and at the same time opening up for the unpredictable, is important.