The Tranolite Period was a period in time for the Aplan civilisation, located on planet Alfava Metraxis in the Dundra system of the Garn belt.
Many architectural wonders such as the Aplan Temple and the Aplan Mortarium were built around this time period.
This period came to a halt after the Weeping Angels rendered the Aplan extinct following their arrival on Alfava Metraxis. (TV: The Time of Angels)