Due to Lessa's being the last Weyrwoman, she and Ramoth were not allowed to fly or train with the weyrlings while R'gul was Weyrleader. The day after F'lar became Weyrleader, the Lords Holder had marched on the Weyr to put an end to tithes, F'lar and the rest of the wings were busy ending this, it was at this time that Lessa took the opportunity to fly on Ramoth for the first time together, after the mating flight the previous day.
A while after that, F'lar taught Lessa and Ramoth to go between, which led to Lessa's discovery that dragons can travel between times, as well as geographic locations. This was the first flight between times in four hundred turns.
Because of the desperate shortage of food in the Weyr, Lessa had sent a young bronze rider, K'net, and his wing out to do some judicious pilfering from the gorged, lazy Holders. F'lar had gone after K'net to put an end to his pilfering, and nearly missed Ramoth's first mating flight and his long-awaited chance to be Weyrleader. Lessa was able to call Mnementh and Piyanth back at the last minute, much to R'gul's annoyance.
Immediately before the mating flight, when Ramoth was going to eat her kill Lessa forced Ramoth to submit to her iron will to blood her kill only, not to eat the hot flesh that would weigh her down in her furious race against the smaller bronzes. Though she began with seven chasers, it came down to R'gul's Hath, T'bor's Orth, and F'lar's Mnemeth. She couldn't stand Hath, but was considering Orth when Mnemeth claimed her, thus making F'lar the new Weyleader.
Ramoth's first clutch produced the gratifying total of 41 eggs, more than 3 times the paltry 12 Jora's Nemorth had always produced. Among the dragons hatched from this clutch were Lioth (N'ton- Fort's future Weyrleader's dragon) and Prideth (Kylara- Southern's future Weyrwoman's dragon).
After Thread had started to fall and the scant 200 dragons were not enough to keep all Pern Threadfree, the need became desperate to somehow repopulate the 5 empty Weyrs. F'lar looked to Ramoth and her queen daughters to solve this, but it was clear that this would take more time than they had. Lessa realised that the opening lines of the Question Song held the answer... "Gone away, gone ahead..."
Lessa realized that the "ahead" referred to between times, 400 years. She believed that the 5 Weyrs had come forward 400 years, to solve the desperate situation in her time. Records already showed that that time was during the last Long Interval, when dragonriders were not needed to destroy Thread. Knowing they would need someone to guide them to the future, Lessa took the coordinates from a 400 year old tapestry of Ruatha, and - against F'lar's strictest orders- she and Ramoth jumped between in a journey far longer than any trip between had ever taken- so long that Lessa became delirious for weeks and Ramoth emerged above ancient Ruatha a pale echo of her former robust self. The then Lord Holder of Ruatha had been so surprised that he sent to his daughter at Fort Weyr for help, and Ramoth and Lessa were brought there.
Ramoth, upon arriving at Fort Weyr, was said to "perch on the fireheights and keen constantly as if she owned them". Lessa also arranged for the creation of the Question Song, so that her younger self could receive the clues she needed to time travel. Lessa later managed to convince the 5 Weyrleaders to bring their Weyr's forward, saving the Pern of 400 years in the future.