During the first year of a screening programme in Cornwall, a rural area of southwest England, 5024 young people were screened for genital Chlamydia trachomatis infection. We used mapping software to assess the prevalence of genital chlamydial infection and access to genitourinary medicine services among 16-25 year olds. Using this data, we calculated that attendance at genitourinary medicine clinics in Cornwall varies between 20/1000 and 83/1000 in this age group. Similarly, the rate of positive results varies between 2.9 and 27.4%, depending on place of residence and testing site. The highest rates of infection were noted in two areas with poor access to existing genitourinary medicine clinics. This information can be used to better plan sexual health services.