BOSTON—Carpenter & Company, Inc. has secured a total of $680 million in construction and equity financing for its 61-story Four Seasons Hotel & Private Residences One Dalton Street, Boston being built in the city's Back Bay neighborhood.

The building, already under construction, when completed will be the tallest constructed in New England since the early 1970s, according to HFF, which arranged the financing for Cambridge, MA-based Carpenter & Co.

HFF worked on behalf of Carpenter & Company, Inc. to secure the $500-million construction loan through London-based The Children's Investment Fund Management LLP. Citi Private Bank raised $180 million in joint venture equity for the project.

The development will consist of 180 high-end private residences on floors 25 through 61 of the building and a 211-room luxury hotel occupying the lower 23 floors. Residents will have full access to all of the hotel's services and amenities, including two restaurants, two lounges and a private health club and spa featuring a 70-foot-long swimming pool located along an exterior glass wall. Both the hotel and residential entrances and lobbies will front a new park being developed across the street and are adjacent to the 10-acre Christian Science Plaza, which provides built-in open space for residents. The project broke ground last month and construction is estimated to continue over a two-and-a-half-year period.

The HFF debt and equity placement team representing the borrower was led by senior managing director Riaz Cassum, executive managing director John Fowler and senior real estate analyst Robyn King.

“One Dalton will deliver an unmatched, super luxury product marked by iconic architecture, a coveted address and walkability to renowned Back Bay shopping and restaurants coupled with Four Seasons' legendary hotel services, top-of-the-line amenities and dramatic panoramic views,” Cassum says. “This is a legacy development, the size and scale of which are unlikely to be duplicated in the city.”

The project was designed by architects Pei Cobb Freed & Partners in collaboration with Cambridge Seven Associates. The City of Boston, when the Four Seasons Hotel & Private Residences One Dalton Street, Boston is completed, will join London, Shanghai, Singapore, Istanbul, New York, Los Angeles, and Chicago to have more than one Four Seasons hotel. The Four Seasons Hotel Boston is located at 200 Boylston St. and features 273 guest room, including 77 luxury suites.