In 1849, Pennsy officials developed plans to construct a repair facility at Altoona.
Construction started in 1850, and soon, several small buildings housed a machine shop, woodworking shop, blacksmith shop, locomotive repair shop, and foundry.
These facilities were later demolished to make room for continuing expansion.

By 1926, the Altoona Works occupied 217.82 acres (88.15 ha) and consisted of four units: the Altoona Machine Shops, Altoona Car Shops, Juniata Shops, and South Altoona Foundries.

The Altoona Machine Shops consisted of over a dozen buildings and performed locomotive repairs, plus made locomotive repair parts and non-metal castings.

The Altoona Car Shops were built beginning in 1869.
By 1926, it included a dozen buildings, built passenger and freight cars, and repaired same.

The Juniata Shops were built out of need for more shop space at Altoona, in 1889.
These shops consisted of 10 buildings, and constructed locomotives and performed heavy repairs of locomotives.

The South Altoona Foundries were built, again, out of need for more space at Altoona, in 1904.
The shops primarily made gray iron castings.

In 1875, the Altoona Works started a Test Department for Pennsy equipment, both built and purchased.
In following years, the Pennsylvania Railroad led the nation in the development of research and testing procedures of practical value for the railroad industry.
Use of the testing facilities was discontinued in 1968.

By 1945 the Altoona Works had become one of the largest repair and construction facilities for locomotives and cars in the world.
Since 1968, many of the structures of Altoona Works were demolished.
In 1849, Pennsy officials developed plans to construct a repair facility at Altoona. Construction started in 1850, and soon, several small buildings housed a machine shop, woodworking shop, blacksmith shop, locomotive repair shop, and foundry. These facilities were later demolished to make room for continuing expansion.
By 1926, the Altoona Works occupied 217.82 acres (88.15 ha) and consisted of four units: the Altoona Machine Shops, Altoona Car Shops, Juniata Shops, and South Altoona Foundries.
The Altoona Machine Shops consisted of over a dozen buildings and performed locomotive repairs, plus made locomotive repair parts and non-metal castings.
The Altoona Car Shops were built beginning in 1869. By 1926, it included a dozen buildings, built passenger and freight cars, and repaired same.
The Juniata Shops were built out of need for more shop space at Altoona, in 1889. These shops consisted of 10 buildings, and constructed locomotives and performed heavy repairs of locomotives.
The South Altoona Foundries were built, again, out of need for more space at Altoona, in 1904. The shops primarily made gray iron castings.
In 1875, the Altoona Works started a Test Department for Pennsy equipment, both built and purchased. In following years, the Pennsylvania Railroad led the nation in the development of research and testing procedures of practical value for the railroad industry. Use of the testing facilities was discontinued in 1968.
By 1945 the Altoona Works had become one of the largest repair and construction facilities for locomotives and cars in the world. Since 1968, many of the structures of Altoona Works were demolished.
Pennsylvania Railroad