The Mayflower Hotel opened on February 18, 1925.
The hotel sat on 1.5 acres (6,100 m²) of land, and had roughly 100,000 square feet (9,300 m²) of interior space.
Several heating oil furnaces and one of the world's largest air conditioning units kept the hotel at an even 70 °F (21 °C) year round.
The hotel's promenade, as completed, was 26 feet (7.9 m) wide and 300 feet (91 m) long.

The hotel had 440 guest rooms, each with its own shower bath.
Guest suites had a sitting room, dining room, bath, and up to seven bedrooms.
The hotel's 500 residential guest apartments each had its own kitchenette, dining room, and drawing room with fireplace.
Some had as many as 11 rooms, and up to five baths.

The cruciform lobby had a mezzanine on the north, west, and south sides, and marble-clad piers divided the north and south walls into three bays.
A small cocktail lounge was located along the north wall, while the reception desk occupied the south wall.
The lobby received light from a coffered skylight.
Four great bronze torchères, hand-wrought and trimmed with gold, dominated the lobby (and were claimed by the hotel to be "priceless").
The main lobby entrance on Connecticut Avenue had a stairway that led down to the first below-ground level, where public restrooms, the barber shop, and a shoeshine stand (made of marble) were located.
A secondary corridor and steps behind the elevators led to the Presidential Room; another secondary corridor to the east of the front desk led to the Mayflower Coffee Shop.
The four elevators to the east of the lobby, joining it to the Promenade, had bronze doors with images of the Mayflower vessel on them.

The Mayflower featured three restaurants.
The 66 by 76 feet (20 by 23 m) Palm Court featured a glass dome supported by iron latticework, numerous palm trees, and a marble fountain and pool with water lilies growing in it.
The 50 by 169 feet (15 by 52 m) Presidential Restaurant was decorated with the seals of the Thirteen Colonies.
Both were located on the main floor.
The Garden Terrace was located on the first below-ground floor.
The Italianate style room featured a coffered ceiling done in copper, a marble fountain, plaster walls in warm pastel tints, alcoves designed to look like arbors, and murals of early Washington, D.C., and nearby Mount Vernon.
Two well-known hoteliers managed the restaurants: Jules Venice, the maitre d'hotel, and Sabatini, former chef at Delmonico's.

The hotel's Grand Ballroom featured a stage with proscenium, beneath which was a hidden thrust stage that could be projected out into the ballroom.
The Grand Ballroom's main entrance was on 17th Street, where a covered, semi-circular carriageway allowed up to three carriages at a time to unload patrons.
The hotel also had several small, private ballrooms for more intimate events.
Next to the ballroom on the 17th Street side was the Chinese Room—a sumptuous meeting and banqueting room inspired by The Peacock Room by James McNeill Whistler.

The Mayflower Hotel's interior design was created by E.S. Bullock of Albert Pick & Co. The furnishings, which cost $1.25 million ($14,943,216 in 2019 dollars), were antique and reproduction pieces in the Sheraton, Louis Quinze, and early Renaissance styles. "
Walls, floors, stairs, pilasters and wainscoting in the lobby and the major function rooms [were] clad in a wide array of American and imported marbles, and ceilings and walls throughout the first floor and mezzanine [were] ornamented by finely cast, low-relief plaster decorations, often further embellished with gold leaf."
The use of gold gilt to trim decoration was extensive; newspapers said the hotel contained more gold trim than any other building except the Library of Congress.
Original artworks, some by quite famous artists, adorned the public spaces.
These included four larger-than-life-sized portraits of the first four presidents by painter and muralist Louis Grell of Chicago.
Three marble statuary groups were also displayed in the lobby and public areas: La Sirene by Denys Puech; Flora by William Couper; and The Lost Pleiad (also known
The Mayflower Hotel opened on February 18, 1925. The hotel sat on 1.5 acres (6,100 m²) of land, and had roughly 100,000 square feet (9,300 m²) of interior space. Several heating oil furnaces and one of the world's largest air conditioning units kept the hotel at an even 70 °F (21 °C) year round. The hotel's promenade, as completed, was 26 feet (7.9 m) wide and 300 feet (91 m) long.
The hotel had 440 guest rooms, each with its own shower bath. Guest suites had a sitting room, dining room, bath, and up to seven bedrooms. The hotel's 500 residential guest apartments each had its own kitchenette, dining room, and drawing room with fireplace. Some had as many as 11 rooms, and up to five baths.
The cruciform lobby had a mezzanine on the north, west, and south sides, and marble-clad piers divided the north and south walls into three bays. A small cocktail lounge was located along the north wall, while the reception desk occupied the south wall. The lobby received light from a coffered skylight. Four great bronze torchères, hand-wrought and trimmed with gold, dominated the lobby (and were claimed by the hotel to be "priceless"). The main lobby entrance on Connecticut Avenue had a stairway that led down to the first below-ground level, where public restrooms, the barber shop, and a shoeshine stand (made of marble) were located. A secondary corridor and steps behind the elevators led to the Presidential Room; another secondary corridor to the east of the front desk led to the Mayflower Coffee Shop. The four elevators to the east of the lobby, joining it to the Promenade, had bronze doors with images of the Mayflower vessel on them.
The Mayflower featured three restaurants. The 66 by 76 feet (20 by 23 m) Palm Court featured a glass dome supported by iron latticework, numerous palm trees, and a marble fountain and pool with water lilies growing in it. The 50 by 169 feet (15 by 52 m) Presidential Restaurant was decorated with the seals of the Thirteen Colonies. Both were located on the main floor. The Garden Terrace was located on the first below-ground floor. The Italianate style room featured a coffered ceiling done in copper, a marble fountain, plaster walls in warm pastel tints, alcoves designed to look like arbors, and murals of early Washington, D.C., and nearby Mount Vernon. Two well-known hoteliers managed the restaurants: Jules Venice, the maitre d'hotel, and Sabatini, former chef at Delmonico's.
The hotel's Grand Ballroom featured a stage with proscenium, beneath which was a hidden thrust stage that could be projected out into the ballroom. The Grand Ballroom's main entrance was on 17th Street, where a covered, semi-circular carriageway allowed up to three carriages at a time to unload patrons. The hotel also had several small, private ballrooms for more intimate events. Next to the ballroom on the 17th Street side was the Chinese Room—a sumptuous meeting and banqueting room inspired by The Peacock Room by James McNeill Whistler.
The Mayflower Hotel's interior design was created by E.S. Bullock of Albert Pick & Co. The furnishings, which cost $1.25 million ($14,943,216 in 2019 dollars), were antique and reproduction pieces in the Sheraton, Louis Quinze, and early Renaissance styles. "Walls, floors, stairs, pilasters and wainscoting in the lobby and the major function rooms [were] clad in a wide array of American and imported marbles, and ceilings and walls throughout the first floor and mezzanine [were] ornamented by finely cast, low-relief plaster decorations, often further embellished with gold leaf." The use of gold gilt to trim decoration was extensive; newspapers said the hotel contained more gold trim than any other building except the Library of Congress. Original artworks, some by quite famous artists, adorned the public spaces. These included four larger-than-life-sized portraits of the first four presidents by painter and muralist Louis Grell of Chicago. Three marble statuary groups were also displayed in the lobby and public areas: La Sirene by Denys Puech; Flora by William Couper; and The Lost Pleiad (also known
Mayflower Hotel