The Kraków Ecology Exhibition, held every year at the Avenue of the Roses as part of Earth Days (21-22 April), draws our attention to threats brought by the rapid development of our civilisation and the disturbed balance between humankind and the environment. Municipal institutions and non-governmental organisations present their activities aiming to improve the cleanliness of the city. There will also be the traditional collection of raw materials in exchange for seedlings of plants and shrubs.