Nedarim 23A

והוו מצטערי רבנן משימשא לטולא ומטולא לשימשא.

and the rabbis were troubled by the fact that they could not dissolve the vow. They spent an extended period of time attempting to do so. During this time, they moved from a location with light from the sun to one with shade, and then moved again from the shade back to the sun.

(לישנא אחרא: אדעתא דהכי? אין. כמה זימנין, והוו מצטערי רבנן משימשא לטולא ומטולא לשימשא. )

The Talmud cites another version of the incident: They asked him: Did you vow with knowledge of this particular fact when you vowed? He said to them: Yes. This occurred several times and the rabbis were troubled with this problem for an extended period of time, during which they moved from the sun to the shade and from the shade to the sun, but they did not find a solution.

אמר ליה בטנית בריה דאבא שאול בן בטנית: מי נדרת אדעתא דמצטערי רבנן מטולא לשימשא ומשימשא לטולא? אמר: לא, ושריוה.

Botnit, son of Abba Shaul ben Botnit, said to him: Would you have vowed with the knowledge that the rabbis would be troubled even to the point of going from shade to sun and from sun to shade? He said: No, and they dissolved it.

רבי ישמעאל בר רבי יוסי הוה ליה נדרא למישרא. אתא לקמייהו דרבנן, אמרו ליה: נדרת אדעתא דהכי? אמר להו: אין. נדרתא אדעתא דהכי? אמר להו: אין. כמה זימנין. כיון דחזא ההוא קצרא דמצטערי רבנן, מחייה באוכלא דקצרי. אמר: אדעתא דמחי לי קצרא לא נדרי, ושריה לנפשיה.

The Talmud relates another incident: R' Yishmael bar R' Yosei had a vow to dissolve. He came before the rabbis. They said to him: Did you vow with knowledge of this particular fact? He said to them: Yes. They asked again: Did you vow with knowledge of this other fact? He said to them: Yes. This occurred several times. When a certain launderer saw that the rabbis were troubled because R' Yishmael caused them difficulty in successfully dissolving his vow, he hit R' Yishmael with a launderer’s tool that he had in his hand. R' Yishmael said: Had I known that the launderer would hit me due to my vow I would not have vowed, and he dissolved it.