The double arches consist of a lower horseshoe arch and an upper semi-circular arch.
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Inside, a horseshoe arch frames the heichal and polychrome columns support the galleries.
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The horseshoe arch, also called the Moorish arch and the Keyhole arch, is the emblematic arch of Islamic architecture.
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The horseshoe arch of Muslim evocation is used, somewhat more closed and sloped than the Visigothic as well as the alfiz.
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The horseshoe arch is based on the semicircular arch, but its lower ends are extended further round the circle until they start to converge.
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The library window is marked by an elegant setting that has two columns flanking the opening, which is a horseshoe arch topped by six blind arches and crowned by a series of berms sawtooth.
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There are two light openings near the top of the main tower, before the roof, with horseshoe arches and cubical capitals enclosed in a single arch.