Altoona, a city of Blair co., Penn., 244 m. by railroad W. N. W. of Philadelphia, and 115 m. E. of Pittsburgh; pop. in 1860, 3,595: in 1870, 10,610. It was laid out in 1849, and is situated at the head of Tuckahoe valley and at the foot of the Alleghanies. It is on the line of the Pennsylvania central railroad, to which it owes most of its prosperity; the workshops of the company situated here are the most extensive in the state. The city contains 11 churches, a high school, 2 banks, 6 hotels, and 3 daily newspapers. At Altoona the western-bound traveller begins the ascent of the Alleghanies. In the course of the next 11 m. some of the finest views and the greatest achievements of engineering skill on the entire line are to be seen. Within this distance the road reaches the summit by so steep a grade that, while in the ascent double power is required to move the train, the entire 11 m. of descent are run without steam, the speed of the train being regulated by the brakes. The summit of the mountain is pierced by a tunnel 3,670 feet long.

On the eastern slope is the famous "horse-shoe bend,11 formed by a very short curve in the road around the brink of a precipitous descent.