The Twin Towers of the original World Trade Center complex in New York were built between the late 1960s and early 1970s, with construction starting in 1966 and completion in the early 1970s.

Key dates

  • Construction on the overall World Trade Center site began on August 5, 1966.
  • The North Tower (1 World Trade Center) structurally topped out and was completed around December 1970.
  • The South Tower (2 World Trade Center) was completed in July 1971.
  • Both towers were officially dedicated and opened on April 4, 1973.

Simple timeline

  • 1966 – Site construction for the World Trade Center begins in Lower Manhattan.
  • 1968–1969 – Main tower construction starts: North Tower in 1968, South Tower in 1969.
  • 1970–1971 – Structural completion of the towers (North in 1970, South in 1971). Tenants begin moving in even before full completion.
  • 1973 – Official dedication of the Twin Towers as part of the World Trade Center complex.

Information gathered from public forums or data available on the internet and portrayed here.