Perthshire, a central county of Scotland, bordering on the counties of Inverness, Aberdeen, Forfar, Fife, Kinross, Clackmannan, Stirling, and Argyle; area (including two small detached portions, one on the frith of Forth, and one surrounded by Stirlingshire), 2,835 sq. m.; pop. in 1871, 127,762. The Grampians form its N. and W. boundary, and rise in the summit of Ben Lawers to the height of 3,984 ft. The county is drained by the Tay and its tribuaries and by the Forth. The Tay flows from the N. E. end of Loch Tay, a lake 16 m. long, and runs circuitously about 100 m. to the firth of Tay, from which it is navigable for vessels of 100 tons as far as Perth. Lochs Earn, Rannoch, and Katrine, with several other beautiful but smaller lakes, are in this county, which is also famous for the wild beauty of the straths or mountain passes and glens. In the low alluvial region of the southeast is one of the finest agricultural districts in Scotland; and in the highland districts are extensive sheepwalks. Linen and cotton are manufactured; and the fisheries on the Tay are the most valuable in Scotland. The county was formerly divided into the districts of Gowrie, Perth, Stormont, Strathearn, Menteith, Breadalbane, Balquhid-der, and Rannoch. The principal towns are Perth, the capital, Crieff, and Dunblane.