The hills of Los Feliz are alive with historic architectural treasures. Some originals are in painstakingly preserved condition, others have been radically updated for the modern era. This big corner lot estate, tucked into the neighborhood’s eastern foothills just below Griffith Park, is one of the latter.

Built in 1928, the authentic English Tudor Revival-style house underwent a complete overhaul circa 2014, when the interior was transformed into a snazzy, contemporary series of light-filled open spaces. The following year, the place was sold for just under $3 million to its current owner, Jonathan Sutton Day — a 30-year-old family member of Bel Air-based billionaire Robert Addison Day, and a direct descendent of prominent philanthropist William Myron Keck, founder of the Superior Oil company. After nearly six years of ownership, Day has apparently tired of the quarter-acre property, offering it on the open market with a $3.7 million pricetag.

Set on a knoll towering high above the street, the home’s architecture is an interesting fusion of old-school half-timbering, red brick, and an industrial-chic contemporary addition down at ground level, believed to have been added during the 1990s, hewn from smooth grey stucco. A long, steep staircase climbs high above the roadside three-car garage and past a sprawling lawn the the 5,000-square-foot structure’s front door.

Inside, the “interior renovations celebrate the modern lifestyle but are extremely kind to the original spirit of the design,” per the listing. There’s a grand living room on the main floor with vaulted ceilings and a marble fireplace, a formal dining room, and a state-of-the-art modern kitchen with a breakfast bar and balcony. Wide-plank oak floors run throughout the home, as do clean-lined, contemporary furnishings.

The multi-level structure also contains the private upper floor, which packs in a sumptuous master suite with sitting area, spa-style bath, walk-in closet, and a slim balcony with views of the surrounding hills. Elsewhere upstairs are two large ensuite guest bedrooms, one of which currently functions as a lavish home office.

To access the lower level addition, there’s a long flight of stairs that leads down, down, down past a bathroom to a large bonus room currently configured as a gym. Two more flights of interior stairs lead down to a tremendous games/media lounge and the three-car attached garage, respectively. Massive stone and concrete retaining walls encircle the fortress-like property.

Nina Chea and J.R. Davidson of Red X Real Estate at Keller Williams hold the listing.