Geography of Kent and Dungeness have been formed by accumulation of alluvium. Kent's principal river, the River Medway, rises near Edenbridge and flows some 25 miles (40 km) eastwards to a point near Maidstone, when it turns north. Here it breaks through the North Downs at Rochester before joining the River Thames as its final tributary near Sheerness. The river is tidal as far as Allington lock, but in earlier times cargo-carrying vessels reached as far upstream as Tonbridge. The Medway has captured the head waters of other rivers such as the River Darent. There are other rivers in Kent, most notably the
Rochester Grammar School Rochester Grammar School Rochester Grammar School (known as Rochester Grammar School for Girls until 2006) often abbreviated to RGS is a grammar school for the education of girls between the ages of 11 and 18. It has academy status. Pupils are expected to perform highly throughout the school. It is now known as just "Rochester Grammar School" following the introduction of boys into the sixth form. Rochester Grammar School is located on Rochester Maidstone Road, opposite the Sir Joseph Williamson's Mathematical School. Their sixth form is mixed but the rest of the school is single-sex. Last year's results moved them