The museum had been closed since March 13 due to the pandemic.
On Friday, 19 years after the terror attack, family members of the victims were able to return.
CLICK HERE for more Eyewitness News reflections, photos and stories marking the anniversary of 9/11
Visitors will notice sanitizing stations and social distancing signs throughout, and capacity will be limited to 25%.
9/11 Museum opens at 10 a.m. and opens five days a week with new health and safety measures in place and ongoing operational changes to ensure a safe Museum experience.
Tickets must be purchased online and in advance.
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