Old avenues, or alleys of trees, form an important part of the cultural landscape. They used to be planted mainly in gardens and parks; later, they started playing an even more important role, particularly in the open areas, and within urban landscapes. Nowadays, they are frequently regarded as inconvenient formations, which exert a negative impact on traffic and impede road construction. However, it is is worth bearing in mind that avenues play a number of crucial functions in terms of climate, ecology and aesthetics, and as such they deserve particular care. The article is devoted to the linden trees planted in an avenue layout along the Nałęczowska street in Lublin town in Poland. The layout currently consists of 85 individual trees in varying health condition, that is, 35% of healthy trees, nearly half exhibiting signs of reduced vitality, and 16% in the state of advanced decay.