late 14c., "to journey," from travailen (1300) "to make a journey," originally "to toil, labor" (see travail). The semantic development may have been via the notion of "go on a difficult journey," but it also may reflect the difficulty of any journey in the Middle Ages. Replaced Old English faran. Related: Traveled; traveling. Traveled (adj.) "having made journeys, experienced in travel" is from early 15c. Traveling salesman is attested from 1885.
1660s, "long speech by one person, scene in a drama in which a person speaks by himself," from French monologue, from Late Greek monologos "speaking alone or to oneself," from Greek monos "single, alone" (from PIE root *men- (4) "small, isolated") + logos "speech, word," from legein "to speak," from PIE root *leg- (1) "to collect, gather," with derivatives meaning "to speak (to 'pick out words')." Related: Monologist.
<a href="https://www.etymonline.com/word/travelogue">Etymology of travelogue by etymonline</a>
Harper, D. (n.d.). Etymology of travelogue. Online Etymology Dictionary. Retrieved $(datetime), from https://www.etymonline.com/word/travelogue