This chapter is concerned with the impact of tourism on the environment. The environment is made up of both natural and human features. Human settlements set within the countryside may contain a large number of attractions for tourists. Often the natural environment is referred to as the physical environment. The natural or physical environment includes the landscape, particular features such as rivers, rock outcrops, beaches and also plants and animals. As with economic and socio-cultural impacts, environmental impacts can be subdivided under the headings positive and negative, with positive impacts being the stimulation of measures to protect sensitive environments, such as national parks, promote the conservation of important parts of the built heritage and provide money via entrance charges to maintain buildings and monuments. More generally, tourism may make tourists more aware of the importance of the environment. However, tourism has had a reputation for creating negative environmental impacts: damage to footpaths, litter, pollution of beaches and rivers, traffic congestion, overcrowding and disturbance to wildlife habitats This chapter discusses both positive and negative impacts via a number of case studies.