The 19 kilometer (11 mile) long Remparts de Marrakech encircles the biggest medina (old Arabic town) in Morocco, which has been on the UNESCO World Heritage Site list since 1985. It is the historical heart of Marrakech. The beautiful minaret of the Koutoubia Mosque, dating from Almohad times, overlooks the medina, whose epicenter is the famous Jemaâ El Fna. The ochre buildings, the hustle and bustle of the markets and commercial streets filled with artisans, and the beauty of the monuments and riads (guesthouses) hidden behind alleyway walls make the medina an enthralling place to visit.