A crane loaded the bronze statues onto a flatbed truck, en route to the city's conservation partner, where they will receive a steam cleaning and a protective wax coating.
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Built in 1893, the "great protectors" require expert care in order to preserve their appearance.
The reinstallation date of the lion statues has not been announced at this time, but they're expected to be back in about a month.
Edward Kemeys designed the sculptures.