The floors hit in the World Trade Center during the 9/11 attacks were as follows:
- The North Tower (1 WTC) was struck by hijacked Flight 11 between floors 93 and 99 at 8:46 a.m.
- The South Tower (2 WTC) was struck by hijacked Flight 175 between floors 77 and 85 at 9:03 a.m.
These impacts caused massive destruction and fires in the upper parts of the towers, ultimately leading to their collapse within hours.