Titus Calestrius Tiro Orbius Speratus was a Roman senator who held a series of offices in the emperor's service.
[2] One is the friend of Pliny the Younger, who was praetor in the year 93;[3] next is the subject of this article; the third is Titus Calestrius Tiro Julius Maternus, governor of Lycia et Pamphylia from 136 to 138[4] and the son of the second.
[5] The cursus honorum of Calestrius Tiro can be recovered in part from a Greek inscription his son erected at Iotape (modern Aytap).
Calestrius Tiro returned to Rome where he advanced through the traditional Republican magistracies of plebeian tribune and praetor.
Once he stepped down from his praetorship, Calestrius Tiro was appointed curator of the Viae Valeria, Tiburtina, and a third road whose name is lost.