Switch Lock

Railroad switch locks are the original purpose of railroad padlocks — securing the throw bar of trackside switches so that only authorized crew with the correct switch key could realign tracks. Switch locks needed to be weatherproof, tamper-resistant, and durable across decades of outdoor service. Brass and bronze were the materials of choice for the lock body because they resisted corrosion better than iron, while steel shackles provided tensile strength. The standard railroad switch lock accepts a hollow barrel switch key, with internal warding cut so that each railroad's keys would only operate that railroad's locks. This was the entire point: a Union Pacific switch key would not turn a Santa Fe switch lock, and vice versa. Switch locks remained in active service into the late 20th century, with many railroads only retiring them when electronic interlocking made manual switch operation obsolete. Browse switch locks catalogued in the archive below.