Discover the ideal blend of modern luxury and historic grandeur at 620 South Allen Ave. Set in San Marino's exclusive Huntington Library District, this distinguished Spanish Colonial Revival estate--originally designed by renowned architect Everett Phillips Babcock--has been masterfully reimagined through a meticulous, multi-year, ground-up renovation completed in 2025. The home has been extensively improved at the infrastructure level, including a new roof, all-new electrical and plumbing systems, new HVAC, insulation, and re-finished windows. Thoughtfully integrated smart-home enhancements include Nest climate control, two high-speed EV charging stations, and a pre-wired security system with CCTV, offering both comfort and peace of mind. Inside, a curated palette of sumptuous finishes defines the living experience, including engineered white oak flooring, imported Italian porcelain tile, bespoke lighting, and custom Italian cabinetry throughout. Designed for both everyday living and elegant entertaining, the chef's kitchen serves as a true centerpiece--appointed with Italian marble countertops, fully integrated Sub-Zero refrigeration, a Wolf 48-inch cooktop with double ovens, and a generous walk-in pantry. The home offers five en suite bedrooms, including a main-level guest suite and four additional bedrooms upstairs. The primary suite is a private retreat of exceptional scale, featuring a custom-built walk-in wardrobe and a spa-inspired bath finished to the highest standard. Set on approximately three-quarters of an acre, the grounds have been reimagined to evoke a private resort setting. Enhancements include new hardscaping, professionally designed landscaping, and a new front yard, backyard, driveway, courtyard, and garage. Outdoor amenities include a refinished championship tennis court with lights, a rebuilt pool and spa with new app-controlled equipment, and Trex composite decking for seamless indoor-outdoor living. A detached guest house includes a 3/4 bath, providing flexible space for guests, a home office, or recreation. The extra-wide circular driveway, off Allen Ave, is spacious enough to comfortably fit 2 cars side by side while a second driveway, off California Blvd, provides added convenience. A rare offering, this 1925 estate captures the romance of its architectural lineage while delivering the sophistication, comfort, and turnkey ease of a newly constructed home.