Lawyer and industrialist Willis Fisher McCook was on top of the world in 1907, the year he built his 30-room manse in Shadyside.

Tony Tye, Post-Gazette The Pittsburgh firm Carpenter and Crocker, which designed the McCook mansion, also were the architects for the house McCook built around the corner for his daughter, Bessie McCook Reed, and her family, at 925 Amberson Ave. The seven-bedroom, three-bath home is on the market for $995,000. Click photo for larger image. More information For an appointment to see the houses at 5105 Fifth Ave. and 925 Amberson Ave., Shadyside, call Peg Lampenfield, Howard Hanna, at 412-361-4000. Additional photographs can be seen at www.howardhanna.com, MLS Nos. 510135 and 510844.

McCook, who was Henry Clay Frick's personal and business lawyer, had his hand and head in the formation or direction of steel, oil, banking and insurance businesses from Philadelphia to Texas. He was a co-founder and, by 1900, president of the Pittsburgh Steel Co.

For his efforts he was handsomely rewarded, and for his family McCook built a grand pile in the Jacobean style, on 1.5 acres at the corner of Fifth and Amberson avenues.

Even by Shadyside standards it was a big house, with eight bedrooms on the second floor for the McCooks and their children. The census shows seven of their nine offspring living with Willis and Mary McCook in 1910.

With knights in armor and medieval castles depicted in stained glass windows and tiles, this storybook mansion must have been an enchanting place in which to grow up. Almost a century later, it remains one of the most lavish, finely crafted and best-preserved interiors of Millionaire's Row.

The house also has its own second-floor chapel, with a vaulted ceiling and stained glass windows portraying the Blessed Virgin and archangels Gabriel and Michael. Although McCook was raised a Presbyterian, he converted to Catholicism when he married Mary Ahl.

"She was a beautiful woman," said Martha Perego, looking at a photograph of Mary Ahl McCook, her grandmother. A retired librarian, Perego keeps a collection of family photographs and newspaper clippings, as well as furniture, paintings and other objects from the McCook house, in her Oakland apartment.

Mary McCook died in 1920; her husband passed away three years later. Several of their children continued to live in the house during the 1920s and '30s, but because it was zoned as a single-family residence, the heirs were unable to convert some of the bedrooms into apartments that would have given them income from the property. The house became an officer's training school for University of Pittsburgh students during World War II, and in 1946 the city acquired it for back taxes, which by then had amounted to $65,000. The zoning was changed soon after, and the house was leased to a woman who converted the upper floors into apartments for veterans and their families.

Enter Emil and Margaret Bonavita, who bought the McCook mansion at a sheriff's sale in 1949 for the bargain-basement price of $28,000. Emil, director of safety services for the Pittsburgh chapter of the Red Cross, probably would have been just as happy in a less ostentatious house.

"My mother-in-law was the drive behind it all," said Marie Bonavita, who married their son, also named Emil, in 1965. Peg Bonavita had a passion for old houses and had often ridden by this one on the trolley. Once ensconced, the Bonavitas removed partitions from the first floor, reduced the number of upstairs apartments to 11, converted the coal furnace to gas and updated the mechanical systems. To support their old-house habit, the elder Bonavitas opened their doors to Carnegie Tech students. Many visual and theater arts students stayed there over the years, including Albert Brooks; among their visitors were the young Shirley Jones, George Peppard and Andrew Warhola.

Tony Tye, Post-Gazette The dining room of the Reed house was restored by the present owners, who stripped off the gray paint that covered the oak paneling, cupboards and even the amber-glass mosaic fireplace surround. Click photo for larger image.

Peg Bonavita lived in the house until her death last Christmas Eve, less than two months before fire struck on Feb. 18. Thought to have been started by a student's surge suppressor, the fire damaged several third-floor bedrooms and part of the roof. But there was only minor damage elsewhere in the house, thanks to Pittsburgh firefighters, who contained the fire quickly and without destroying most of the building's many windows.

In the late 1960s, the Bonavitas purchased the red-brick Tudor house next door, at 925 Amberson Ave., which the McCooks had built for their first child, Bessie McCook Reed, and her family just before their own house went up.

Emil and Marie Bonavita, who have lived there since 1971, were planning to move into the big house after his mother's death. The fire changed that; they decided instead to put both houses on the market, at $1.4 million for the mansion and $995,000 for their seven-bedroom, three-bath home.

Both were designed by the Pittsburgh firm Carpenter and Crocker. For the big house, the architects worked in rough-cut gray granite. Today, its black veining is still visible under a layer of Pittsburgh soot that lends gravitas to a lively, asymmetrical design.

Named for James I, who succeeded Elizabeth I in 1603 and was the first monarch to rule both England and Scotland, the Jacobean style flourished in the early 20th century as American architects looked abroad to historical styles for inspiration. The McCook house's battlements and Dutch gables and gable ends mark it as Jacobean, a style that may have been favored because of McCook's Scotch-Irish ancestry. His great-grandfather, George McCook, emigrated from County Antrim to Delaware in 1780.

The front doors open onto the cavernous main hall, which takes on a warm glow from the spectacular, semicircular bay of tall, curved, amber stained-glass windows at the bend in the grand staircase. When the McCooks lived in the house, the room was sparingly furnished with an Oriental carpet, table and a few chairs -- all easily moved for the many dances, weddings and coming-out parties held there. Like much of the first floor, the main hall is paneled and floored in dark, quarter-sawn oak. Tucked away in one corner is the fireplace, with a tile surround depicting a castle and two knights -- a threatening one on a rearing black horse and a protective one standing next to a woman. Might she be James I's mother, Mary, Queen of Scots, and the castle Fotheringhay, where she was tried and beheaded? The house is full of such mysteries waiting to be unraveled.

For a Christmas dance the McCooks hosted around 1908 for daughters Martha and Margaret, the hall was transformed into a ballroom "festooned with laurel tied with red ribbons," reports one of Perego's news clippings. The fireplace was "banked with poinsettia and holly" and a huge Christmas tree stood in the adjacent billiard room, which, along with the library, stands to the left of the hall.

To the right is the Neoclassical parlor, a light and airy contrast to the dark oak of the other rooms, with fluted Ionic pilasters framing the walls. On the floor plan, the architects specified the room be painted in "white enamel with gold," and the McCooks furnished it sympathetically in the delicate, gilt style of Louis XIV.

Also to the right is the dining room, with an elaborately carved oak overmantel, plasterwork pendant ceiling and stained glass windows, including one that depicts a knight or page wearing the cross of St. George, patron saint of England. A photograph of the room, with Katharine McCook's bridal party at their wedding dinner, appears anonymously on the cover of the 1976 cookbook, "The Flavors of Pittsburgh."

The house is not protected by historic designation, and the Bonavitas say they won't sell to someone who intends to tear it down. Two potential buyers are considering converting the big house to condominiums, which could trigger significant changes to the well-preserved rooms on the first floor.

But for imaginative investors, there are other options. Like its neighbor Sunnyledge, the house would make an outstanding boutique hotel, and could once again host weddings and parties. And for the rare big family with a big heart and bigger wallet, it would make one fabulous starter castle.