Time Portal

, also known as Time Holes, are portals scattered across OoA: in.

Location and Uses
When activated, Time Portals can be used to travel back and forth through time. Nayru, the Oracle of Ages, has the ability to create Time Portals. On his adventures, Link must use them to travel between the past and the present, using the powers of Nayru's Harp of Ages and Tune of Echoes to open the portals. Time Portals are marked on the Overworld Map. A total of ten portals can be found across Labrynna (three in the past, seven in the present). Portals are most prevalent in Lynna City, Talus Peaks, Crescent Island and Rolling Ridge.

History
Time Portals are encountered for the first time in the opening sequences of the game, when Veran possesses Nayru. Veran makes her escape by creating a Time Portal using Nayru's powers. She is followed in hot pursuit by Nayru's loyal friend and protector, Ralph. Link has no choice but to follow suit, and thus steps into the world of the past for the first time. As Link obtains the Harp of Ages and the Tune of Echoes, Time Portals become essential to Link's adventure through time. However, Link will encounter fewer portals as he proceeds on his quest. By this time, however, the young hero will have learned to play the Tune of Currents and the Tune of Ages, which allow him to travel forwards and backwards in time without the use of physical portals.

Trivia

 * At least one of the Time Portals - the one to the immediate east of the Maku Tree - was opened by Veran using Nayru. However, an inactive Time Portal can be seen next to Nayru's house even before meeting her for the first time, which suggests that at least this portal, and perhaps the others as well, were created before Veran's arrival. What they might have originally been used for is unclear.