For many Western visitors, the narrow white-washed streets of the walled Medina are themselves a main attraction. Crammed with elaborate mosques such as the Gurgi and the Karamanli, and dotted with the traditional dwellings - many with internal courtyards - that date back to the Ottoman period, the ancient city will draw you back time and again. While there are plenty of up-to-date attractions; including a water park, a zoo, and a collection of beaches, it is the sheer breadth of Tripoli’s historical monuments that make this a unique destination. The gargantuan and imposing Marble Arch dedicated to Emperor Marcus Aurelius offers visitors a final trace of Libya’s Roman period, while Green Square, near the waterfront, provides ample opportunity to simply sit and people-watch. Constructed over many centuries, and complete with harem, mosque and myriad courtyards, it is perhaps the city’s so-called Red Castle (Assai al-Hamra) that truly brings the past to life. This fabulous citadel, which houses the important Jamahiriya Museum, was once the home of the Ottomans and the Knights of St. John and remains the single most important historical landmark in Tripoli.