<P> The interior is occupied by iron stairs that spiral up the walls , with an elevator in the center , both supported by eight iron columns , which do not support the stone structure . The stairs contain fifty sections , most on the north and south walls , with many long landings stretching between them along the east and west walls . These landings allowed many inscribed memorial stones of various materials and sizes to be easily viewed while the stairs were accessible ( until 1976 ) , plus one memorial stone between stairs that is difficult to view . The pyramidion has eight observation windows , two per side , and eight red aircraft warning lights , two per side . Two aluminum lightning rods connected via the elevator support columns to ground water protect the monument . The monument 's present foundation is 37 feet ( 11.3 m ) thick , consisting of half of its original bluestone gneiss rubble encased in concrete . At the northeast corner of the foundation , 21 feet ( 6.4 m ) below ground , is the marble cornerstone , including a zinc case filled with memorabilia . Fifty American flags fly 24 hours a day on a large circle of flag poles centered on the monument . In 2001 , a temporary screening facility was added to the entrance to prevent a terrorist attack . In 2011 , an earthquake slightly damaged the monument , mostly the pyramidion . </P>
<P> The interior is occupied by iron stairs that spiral up the walls , with an elevator in the center , both supported by eight iron columns , which do not support the stone structure . The stairs contain fifty sections , most on the north and south walls , with many long landings stretching between them along the east and west walls . These landings allowed many inscribed memorial stones of various materials and sizes to be easily viewed while the stairs were accessible ( until 1976 ) , plus one memorial stone between stairs that is difficult to view . The pyramidion has eight observation windows , two per side , and eight red aircraft warning lights , two per side . Two aluminum lightning rods connected via the elevator support columns to ground water protect the monument . The monument 's present foundation is 37 feet ( 11.3 m ) thick , consisting of half of its original bluestone gneiss rubble encased in concrete . At the northeast corner of the foundation , 21 feet ( 6.4 m ) below ground , is the marble cornerstone , including a zinc case filled with memorabilia . Fifty American flags fly 24 hours a day on a large circle of flag poles centered on the monument . In 2001 , a temporary screening facility was added to the entrance to prevent a terrorist attack . In 2011 , an earthquake slightly damaged the monument , mostly the pyramidion . </P>
how many flags are around the base of the washington monument
how many flags are around the base of the washington monument
Fifty
Fifty