A bird's eye view of obelisk is square and this structure has gradually tapering four sides and its ends in a pyramidal top.
Obelisks originated with the holy stone of sanctuary which served the sun god, Ra, in Heliopolis. There usually was a pair in front of a gate or sanctuary, and on each side of obelisk there were written hymns and some actions of the of king in hieroglyphics.
Obelisks can have interior spaces.
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