Owjela was the best place which Islamic religion started. The time when was Khalifa Othman Bin Afan, an Arabic leader named Abdullah Bin saad Aby Sareh visited it when he was return from (Azwelah) one of the Fezzan oasis and it said that he lived and died in Owjela in a year 647, and in Othman rule the trade was getting worse, that's why the people were moving from it.

Owjela contains an old mosque, which is the famous and biggest mosque in the history. It had been built when the Islamic liberal were there. The old mosque was built in an area of 456 m2. There are many rooms for learning Koran and studying Koran. They built with local materials with best and beautiful civil engineering, on the top of the mosque there are holes it keeps the temperature normal.

In addition to the old mosque, the Castle is very old one too which located on the north east of the old city. At each corner of the building there is strong circle building which the Italian used it as defend castle.

Old Grave Yards: There are many old grave yards, one of them called Romanian grave and others are Islamic graves and the famous one called (Ghozat grave) and the reason is because there was a war between unknown fighters and people who lived there, and when they win they buried the enemy there.