For individuals inclined toward opulent living and possessing nearly $6 million to invest, the sky-high penthouse at The Sudbury in downtown Boston provides an enviable sanctuary elevated above the urban hustle and bustle. Boasting four bedrooms and lavish amenities, the residence at 110 Sudbury St. is on the market for $5.99 million, according to boston.com.

Perched on the top floor, Unit 4301 not only provides sprawling southwest views of the Back Bay skyline and the glistening Charles River, but it also comes to fully take advantage of its position with picture windows and a floor plan designed for openness and flow. Included in the square footage are three full and one-half bathrooms, confirmed Tracy Campion, Bill Gehan, and Simona La Posta of Campion & Company Fine Homes Real Estate, the team responsible for the listing. The open living area features a stone surround gas fireplace, directly tying into the dining space, and a sleek kitchen -- its custom Scavolini cabinetry and Carrara quartz countertops mentioned by Campion & Company.

Residents have access to some 25,000 square feet of amenities. These include an outdoor heated pool with cabanas, a fitness center, a yoga studio, a sports simulator, and a sky lounge. The building offers round-the-clock concierge services, a club room, and a rooftop garden for homeowner exclusivity.

The primary suite, features built-ins, panoramic windows, and commanding views of the Charles River. The en-suite bathroom, complete with a double vanity, soaking bathtub, and separate shower, promises a spa-like experience. The guest wing is its sanctuary, housing two bedrooms and bathrooms, a laundry room, and a study -- which can alternatively serve as a fourth bedroom -- sporting its river vistas, "Boston's newest high-rise," as described by Campion & Company. The future owners will enjoy two self-park direct-access parking spaces.