FIRST LOOK: Rendering of Amazon HQ2's 'Helix' building in Arlington The plan, which includes a 370,000 sq. ft. spiral-shaped building known as the Helix, is scheduled to open by 2025. Author: Matthew Torres Updated: 6:22 PM EST February 2, 2021 ARLINGTON, Va. — More than two years after announcing its plan to build a second headquarters in Arlington, Amazon has released the latest designs in its next phase of development with the goal of setting a new standard in mix-used space within the city. The Seattle-based tech giant sent the latest designs for more retail, office and public space to the Arlington County Board on Tuesday in hopes of receiving approval and breaking ground by early next year.