On the heels of Parson Corporation's announcement of the relocation of its corporate headquarters to Washington, D.C., construction is beginning for a mixed-use complex on the Pasadena property that the engineering firm currently calls home.

The 100 West Walnut development, which is being developed by LPC West and AMLI Residential, will replace 6.4 acres of surface parking with multiple five-story structures featuring 400 apartments, 210,000 square feet of office space, and 17,500 square feet of shops and restaurants atop three levels of subterranean parking.

Architecture firms SOM and Harley Ellis Devereaux are designing the development, which will include a number of paseos and shaded arcades cutting across the property, breaking up its unwieldy footprint.

The project is described as a "mixed-use urban village," similar in scale and character to neighboring Old Town Pasadena and other nearby developments, including new apartments and hotels along Walnut Avenue.

LPC West - a subsidiary of Lincoln Property Company - acquired the Parsons property in 2011 for $320 million.