Portland, Isle of, is actually a peninsula connected with the Dorsetshire coast at a point 4-1/2 miles south of Weymouth by the shingle ridge known as the Chesil Bank. It has an area of 2,890 acres, a length of 4-1/2 miles, and a breadth of 1-3/4 miles. The soil is fertile, and the sheep bred here are noted for mutton; but the beds of oolitic Portland stone are the chief source of prosperity, apart from the business created by the harbour of refuge completed by convict labour in 1872. Two strong forts defend the place, and a castle erected by Henry VIII. still exists. Off Portland Bill flows a strong and dangerous current separating the Shambles Bank from the shore.