Nazir 1:6

If a person says that he is a nazir for the amount of time it takes to travel from there to some other place, they estimate how long such a trip would take. If it’s less than 30 days, he is a nazir for 30 days. If the trip takes longer than 30 days, he is a nazir for that period of time.

Nazir 1:7

If one says that he is a nazir like the number of days of the sun, he is a nazir for 365 30-day periods (just over 30 years). Rabbi Yehuda says that such a case happened and when the person completed all of his nezirus periods, he died.