TRAVEL TIME is a measure of how long it takes to get somewhere. But actually expending those minutes is to convert the travel time into time-travel, as the traveler moves across space-time.
We live in the center of a personal space, which has its own, relative time to get to anywhere else. Time horizons exist for events that occur in locations too remote to be sensed in the normal course of life.
Almost everyone currently living, for example, will never know that I exist because of limitations in time-travel.
Thwarticus 