The phrase "time long past" can be replaced with a variety of synonyms that express the concept of a distant and historical era. Terms such as "bygone era," "days of yore," "ancient times," or "olden days" all convey the idea of something that occurred many years ago. Other possible synonyms may include "antiquity," "distant past," "remote times," "historical period," "time immemorial," or "days gone by." The choice of synonym will depend on the context of the sentence, the intended tone, and the writer's personal preference. Regardless of which term is used, each one evokes a sense of nostalgia and curiosity about times that can never be recovered.