Perhaps this can be helpful (see also its references):

On Image Classification: City Images vs Landscapes

Perhaps these can be helpful (see also their references):

Aditya Vailaya , Anil Jain , Hong Jiang Zhang, On Image Classification: City Images vs Landscapes (1998)

and the more recent:

Li Fei-fei, Pietro Perona, A Bayesian Hierarchical Model for Learning Natural Scene Categories (2005)