Red Pyramid

The Red Pyramid of Dahshur
Location within Egypt
Sneferu
Coordinates	29°48′30″N 31°12′21″E / 29.80833°N 31.20583°E / 29.80833; 31.20583Coordinates: 29°48′30″N 31°12′21″E / 29.80833°N 31.20583°E / 29.80833; 31.20583
Type	True Pyramid
Height	105 metres (344 ft)
Base	220 metres (722 ft)
Volume	1,694,000 cubic metres (59,823,045 cu ft)
Slope	43°22'

The Red Pyramid, also called the North Pyramid, is the largest of the three major pyramids located at the Dahshur necropolis in Cairo, Egypt. Named for the rusty reddish hue of its red limestone stones, it is also the third largest Egyptian pyramid, after those of Khufu and Khafra at Giza. It is also believed to be Egypt's first successful attempt at constructing a "true" smooth-sided pyramid. Local residents refer to the Red Pyramid as el-heram el-watwaat, meaning the Bat Pyramid.

The Red Pyramid was not always red. It used to be cased with white Tura limestone, but only a few of these stones now remain at the pyramid's base, at the corner. During the Middle Ages much of the white Tura limestone was taken for buildings in Cairo, revealing the red limestone beneath.

The Red Pyramid was the third pyramid built by Old Kingdom Pharaoh Sneferu, and is located approximately one kilometer to the north of the Bent Pyramid. It is built at the same shallow 43 degree angle as the upper section of the Bent Pyramid, which gives it a noticeably squat appearance compared to other Egyptian pyramids of comparable scale. Construction is believed to have begun during the thirtieth year of Sneferu's reign. Egyptologists disagree on the length of time it took to construct. Based on quarry marks found at various phases of construction, Rainer Stadelmann estimates the time of completion to be approximately 17 years while John Romer, based on this same graffiti, suggests it took only ten years and seven months to build.

Archaeologists speculate its design may be an outcome of engineering crises experienced during the construction of Sneferu's two earlier pyramids. The first of these, the Pyramid at Meidum, collapsed in antiquity, while the second, the Bent Pyramid, had the angle of its inclination dramatically altered from 54 to 43 degrees part-way through construction.