The Mezquita (with its courtyard) is said to be the biggest mosque in the world (600x430 ft). A circuit of its wall is thus 0.4 miles (or more), part of it uphill. Allowing for heat and many stops (some in shops) it should take at least 1/2 hour for a study. Save the Puerta del Perdon for last and cool off inside. You can sit in the Patio de los Naranjos.The oldest door is S. Esteban, midway on the West side(8C)(no picture). It is "original".The other have been much restored (or modified). Of Moorish style they are variants on a theme: a horseshoe or round entrance arch with a rectangular frame (alfiz), alternating voussoir stripes of reddish brick or stone,an echoing arcade above the frame with colonettes and lateral screened windows. An infinite variety of mostly linear designs is present in the panels that subdivide the area with almost no repetition. If enumerated they would fill several pages.