Rittenhouse Square's last remaining undeveloped parcel is shaping up to be the Center City park's most extravagant project yet.

The Laurel, a 48-story ultra-luxury apartment tower, broke ground on Thursday after years of revisions to the design at 1911 Walnut St.

Southern Land Company, the Nashville-based developer that acquired the property in 2015, revealed dazzling renderings of the $300 million tower, which will become the tallest all-residential building in Philadelphia when completed.

“We are thrilled to celebrate this milestone with many of our city and community partners, with whom we have worked closely to make this project a reality,” said Dustin Downey, senior vice president of multifamily development at Southern Land Company. “As the last undeveloped parcel on Rittenhouse Square, we spared no expense to ensure it will surpass everyone’s expectations when it comes to design, amenities and service for our future residents.”

Source/Southern Land Company Rendering of lobby at The Laurel.

Working with community members, the developers ensured that the project will preserve the adjoining historic Warwick Apartments and Rittenhouse Coffee Shop.

The Laurel's updated plan will feature 74 condominiums with a mix of short- and long-term residences with separate lobbies and entrances. Another 24,000 square feet of high end retail will wrap around Walnut, Sansom and 20th streets.

Source/Southern Land Company Rendering of apartment at The Laurel.

"Southern Land Company is redefining urban, luxury living in Philadelphia with The Laurel,” said Clara Wineberg of designer Solomon Cordwell Buenz. "Our design for this project pays homage to the historic context of Rittenhouse Square while also embracing a more modern approach to complement the neighborhood."

Amenities at The Laurel will include valet parking, an indoor lap pool and hot tub, a fitness center, steam room and sauna, club room and conference room, and a yoga and Peloton cycling room. Even dogs will have a spa to call their own.

A terrace overlooking Rittenhouse Square will offer residents a bar and catering kitchen.

Source/Southern Land Company Rendering of pool at The Laurel.

The Laurel will offer residences with prices starting around $2.5 million. Full-floor penthouses are also available.

Prospective buyers who stop by The Laurel's sales center will take virtual tours of the various units on a 12-foot interactive video wall, the first of its kind in Philadelphia.

“We felt it was important to invest in this technology so our residents can truly experience what life at The Laurel will be like from sunrise to sundown,” said Brian Emmons, who is overseeing development of The Laurel. “Since our sales center opened this spring, we have been accepting a steady stream of deposits and anticipate even further excitement once construction is underway.”