CARLSBURG, a circle in the Austrian province of Siebenburgen. It extends over 2500 square miles, or 1,600,000 acres, comprehending one city, three market-towns, and a hundred and seventy-five villages. It is a district rich in the products of agriculture, in corn, pulse, and fruits, especially vines. It furnishes much cattle and game, as well as fish; and it contains mines of rock-salt. It is watered by the rivers Maros and Vulkui, the latter of which yields gold by washing its sand.