Grad je podignut kraj XIV ili početkom XV stoljeća na ušću Unca u Unu. Gradski bedemi porušeni su do temelja, a sačuvala se samo obla kula visoka oko 10 metara, u koje su etaže odvojene svodovima. U historijskim izvorima prvi put se spominje 1431. godine, kada ga je ugarski kralj Sigismund založio Nikoli Frankopanu. Udovica Anžu Frankopana je 1436. godine stanovala jedno vrijeme u Rmnju i potpisivala se kao kneginja Rmanjska. Sredinom XV stoljeća dobio ga je Juraj Frankopan. U ovom se gradu 1451. spominje „sudac“ i „bratstvo purgari“. Rmanj se spominje još 1504. godine među gradovima koje je trebalo popraviti i bolje utvrditi. Ubrzo poslije ovog posljednjeg spomena Rmnja grad je 1524. godine došao pod osmansku vlast. Da li je Rmanj razrušen još tada prilikom osvajanja ili kasnije, za sada nema podataka. U Konobi-Rmnju na Uncu spominje se 1386. godine katolički samostan i postoji mišljenje da je to bio benediktinski samostan, koji je poslije Hasan-paša Predojević predao pravoslavnim kaluđerima.

The town was built in the end of the 14th century and the beginning of the 15th century at the mouth of Unac to Una. Town ramparts were destroyed completely  and all that has been saved is rounded tower 10 meters high. In sources for the first time it was mentioned in 1431 when the Hungarian King Sigismund pawned it to Nikola Frankopan. The widow of Anžu Frankopan in 1436 lived for some time in Rmanj and introduced herself as Duchess of Rmanj. In the middle of the  the 15th century Juraj Frankopan got this town. In 1451 in this town were mentioned „Judge“ and „Purgari Brotherhood“. For the last time Rmanj was mentioned in written sources in 1504 as town that needs be repaired and fortified. IT is known that it fell under the Turkish authority in 1524. What is not known is ifi it was destroyed then or later. In tavern Rmanj people talk about Catholic monastery from 1386 and there is a thought that it  was Benedictine monastery which Hasan-Pasha Predojević gave letter to Orthodox monks. 

Tekst i slike obradio: Igor Pečenković, dipl.ecc.hot. 

Izvori: Stari gradovi Bosne i Hercegovine, Stari gradovi Unsko-sanskog kantona, „Zavod za zaštitu kulturnog naslijeđa USK“ Bihać