Immerse yourself in the timeless elegance of 458 Marine Street, located on the coveted 400 block of West Marine in central Boulder. Step inside and be captivated by the tranquil interior, touches of exposed brick, and an incredible light-filled space. Situated on a generous 10,000+ SF lot, this updated west Boulder home with a newly-built detached guest house offers gorgeous views, seamless indoor/outdoor living, and unparalleled access to amazing trails, CU, and downtown restaurants and shops. From this peaceful, tree-lined street, the front porch beckons you in and the house flows effortlessly, with a dining space off the airy, bright kitchen, plus a bonus sitting room and office at the front of the house. The entertainer's kitchen features stainless steel appliances, custom cabinetry, and a flagstone-topped island that combines both style and functionality. The spacious south-facing living room floods with light through large picture windows, featuring vaulted ceilings, and a perfectly framed fireplace. Upstairs, enjoy an expansive primary suite with a five-piece bathroom, walk-in closets, and a covered balcony retreat with beautiful views. Two more bedrooms and a second full bath complete the upper level. The bright, finished basement has high ceilings and egress windows, welcoming movie nights, workout space, and more! Enjoy time with friends and family in the enchanting backyard, with bountiful shade from mature trees, flagstone dining patio, foothill views, and beautiful landscaping. To the back of the lot, the spacious guest house is a world unto itself, with vaulted ceilings, a private porch, and a comfortable living/dining/flex area. (Convert to a garage if Buyer prefers). Come and write the next chapter of your story at 458 Marine, where you can access the very best of Boulder right outside your door, and always enjoy retreating home to this remarkable property. (Solar panels, new roof and interior paint, refinished floors and updated systems throughout).