A rare new construction offering in Lyon Village, 3108 Key Boulevard presents a well executed residence on one of the neighborhood's most desirable tree lined streets. Set on a level, evenly shaped lot in the heart of Lyon Village, the home offers approximately 6,010 square feet across four finished levels, combining scale, privacy, and exceptional walkability to parks, Metro, schools, trails, and neighborhood dining. The main level is centered around a well executed kitchen and living space designed for both everyday use and entertaining. The kitchen features custom inset cabinetry, a 48” Wolf range, Sub Zero refrigeration, Cove dishwasher, and an oversized island that serves as a natural gathering point. The adjacent family room opens to a screened porch with fireplace and connects seamlessly to the rear patio and yard. The primary suite includes a sitting area, dual walk in closets, and a marble bath with glass shower, along with private views that are uncommon within Lyon Village. Secondary bedrooms are all en suite. The third level loft offers flexible living space with an additional bath and covered porch. The lower level includes a recreation room with wet bar, fitness space, and a guest or au pair suite with walk up access. Additional features include Marvin windows, spray foam insulation with Rockwool sound separation, 10 foot ceilings on the main level, elevator ready construction for future flexibility, an attached garage, and an oversized paver driveway. Built by Rock Spring Homes, a local boutique builder whose principals have lived in Arlington for over 40 years and bring more than 30 years of building experience, with over 100 new homes completed, the residence reflects a consistent focus on quality, proportion, and long term livability.