Girton College is situated, famously, over two miles away from the centre of town. This is due to its history as a women’s college: the University authorities didn’t want male students to be distracted, and so placed the first women’s college as far away as University statutes allowed.
History aside, Girton’s distance doesn’t affect your student life at all: if anything, it improves it, creating an unusually tight-knit student community. Town is at most a 15 minute cycle in, and regualr buses provide access to town each day.
If you have mobility issues which you believe may limit you at Girton, contact both the Admissions Office and the Cambridge University Disability Resource Centre, who are able to make reasonable adjustments for you, which can include discounted taxis, and the right to drive a car as a Cantab.