James Piatt Sr. came to this Central Illinois territory in 1829 and called the area Piatt's Point. In 1837, a plat was registered by Piatt and it was named Monticello by Major James McReynolds, an admirer of Thomas Jefferson.

Industry progressed with the incorporation of the Monticello Railroad Company in 1861 and by the 1880's, Monticello was a major business hub in Central Illinois.

Monticello joined the patent medicine boom in 1893 with the founding of the Pepsin Syrup Company by Harry Crea and Dr. W. B. Caldwell. They were later joined in partnership by John Hott and A. F. Moore. Dr. Caldwell's Syrup Pepsin, an early laxative, was one of the notable patent medicines produced in Monticello. Later brand recognition products among the Caldwell product line was Fletcher's Castoria and Campho-Phenique. In 1925, Moore and Hott sold their Pepsin interest to Sterling Products Company for $5,000,000.

The continual success of the company helped spawn the construction of mansions on North State Street that became known as "Millionaire's Row.

402 North State Street	Queen Anne Victorian Notice the elaborate gingerbread at the porch and gables in the wagon wheel motif. Included a variety of wood siding patterns, including fish scales. Also classical detailing on the window frames.
412 North State Street	Queen Anne with Neo-classic influences. Features include hip roof, flared gables and conical tower. Notice the variety of window sizes and groupings. Detailing is neo-classic. Doric porch columns. Allen Moore and John Hott families are among former owners.
506 North Charter Street	Queen Anne with Neo-classic Hip and gable roofs. Grouped windows. Neoclassic wrap-around porch with radiused corner, crown moldings and scrollwork in pediment. Ionic columns. Corbeled chimney. Built in 1905 by Henry Timmons.
520 North Charter Street	Italianate Victorian Steamboat Victorian porch. Hip roof with flat eaves and decorative brackets. Segmented arch windows and doors with wooden eyebrows. This was the home of Lena Bragg, librarian at Allerton Library for over 40 years.
802 North Charter Street	Italianate Neo-classic Originally designed as a square Italianate with a hip roof. The wings and porches were added for symmetry, giving the home a Neo-classical look. Two level portico supports pediment. Colonial detailing and railings.
844 North Charter Street	Carpenter Gothic. One of the oldest homes on North Charter Street. Wrought iron fence added in 1960.
1004 North State Street	Elizabethan with Prairie School influence. Irregular massing, variety of window types. Eclectic mix of brick, stone, wood and stucco. Original house was Victorian farmhouse, built in 1875. Half-timbering, window patterns, gable pendants, rafter tail and brackets are Elizabethan. Corinthian pilasters flank entry door and side lights. Smokehouse is original. Remodeled in 1917. Flared brick porch piers with stair walls and urns are Prairie Style with geometric motifs repeating in the limestone and wood detailing. Original owner was H. V. Moore, founder of Monticello Moore State Bank, the first bank in Piatt County. The house was later remodeled by son, Dwight Moore. It has remained in the Hutson family since they purchased it in 1933.
1001 North State Street	English Tudor Rambling manor includes gables and crenellated tower. Brick first floor with half-timber and stucco second floor. Extensive use of stone at entrance. Twenty-four room mansion with ornately sculpted ceilings and imported Italian marble fireplaces. Built in 1924 at a cost of $150,000 by Bradford Moore. Shared formal flower gardens, maze gardens, reflecting pools, fountains, a 2,000 sq. ft. green house, carriage house and golf course with his father's home to the north. Father, Allen Moore, made his fortune in the commodities market, as a banker, and as partner of the Dr. Caldwell Pepsin Syrup Co., Mr. Moore also established the Camp Creek Duck Farm, a local landmark. Upon his death, Allen Moore's home became Monticello's first hospital which was later replaced by the current John and Mary Kirby Hospital.
916 North State Street	Neo-classical Simple symmetrical massing with large single windows. Cubic form is often found in Illinois. Ornamental, centered window grouping at second floor. Palladian window in broken pediment at dormer. Columns are combination of Tuscan and fluted Doric, corner pilasters and dentils are classical details. Current owner is Donn Piatt, great, great grandson of James Piatt, one of the city's founders.
915 North State Street	Victorian Gothic Revival Cruciform plan with two interesting gables. Steep roof pitch, large eaves and tall bundled chimneys. Long slender windows with both segmented and full arch windows as well as Victorian bay. Eleven foot ceilings. The window in the dining room at the southeast corner of the house is the only wide window, added 25 years later. Notice the quatrefoil motifs on the ornate porches. Built in 1873 by banker William Houston. Later purchased by Andrew Dighton, a man who was often described as looking a lot like the house; "tall, thin and dignified"! Said to be first local home to have electricity, running water and central heat. The garage and conservatory were artfully added in the 1980's.
902 North State	Queen-Anne Victorian Built as a Victorian farmhouse. The Queen Anne portion was added on. Notice unusual corner orientation with bay window/turret. Variety of window shaped and siding styles, particularly in gables. Victorian turned porch posts and window trim. Built in late 1800's.
810 North State Street	Neo-Georgian Center section is flanked by two massive wings. Strong symmetry, repeated single windows. Two story, semicircular portico is topped with a turned baluster railing. Entry has half-round transom and classical wood surround. Large chimneys. Paired pilasters are used in porte cochere and sunporch wings. Notice the detail, brick lintels with keystones, dentils, brackets and piers with urns at corner. Interior wood is solid walnut. Elegant sweeping staircase, detailed chandeliers and intricate cornice work.
807 North State Street	Victorian Farmhouse Original form is simple with steep gables. Tall slender windows have Victorian trim. Two story bay window. Entry porch columns were added later. The home has been owned by a descendant of one of Monticello's original settlers, John Britton.
719 North State Street	Queen Anne with neo-classic details. Strong, simple massive form with variety of window styles and groupings. Large porch consists of massive, quoined brick piers and turned balusters with Ionic columns and headed by keystone. Broken pediment dormer with half round window. Dentil and decorative scrollwork trim. Interior woodwork and crown moldings are birch, butternut, oak and cherry; all stained to match. Original bath fixtures remain, with some heart-shaped lavatories and large tubs. Original central vac system and ice door on Wilson Street still operable! There is a ballroom in the basement level. The home was built in 1906 by Louis and Mary Dighton Burgess. Mr. Burgess was the founder of the Piatt County Republican Newspaper. Mrs. Burgess was the twin sister of William Dighton who built his home at 712 North State and the daughter of Sarah Dighton who lived next door at 707 N. State. A sidewalk connected the back doors so mother and daughter could enjoy easy visiting privileges.
712 North State Street	English Tudor Massive irregular forms. Mixture of materials with brick base and first floor, half-timber and stucco second story. Massive timber used at porches, sunporches and at porte cochere. Grouped, small divided light windows throughout. Large chimneys. Designed for Dr. Knott with many of the interior features crafted in Europe. In 1916, current owner, William Dighton, Monticello banker and farmer, had the house enlarged and redesigned by Chicago architect Frederick Perkins. Large entry hall has oak walls. Seven bedrooms, two being master bedrooms with attached sleeping porches. Five fireplaces. Basement has oak paneling and hard wood floors. Two staff bedrooms off back stairwell. Coachman lived in finished room with half bath in the three-story carriage house.
707 North State Street	Queen Anne with neo-classic details. Irregular massing with distinctive gambrel roof forms and wrap-around siding. Round columns, dentils, brackets and turned balusters are neoclassic details. Variety of window styles and groupings using large expanses of glass. Notice the roof railings and gingerbread trim. Built in 1898 by William Dighton for his widowed mother, Sarah Dighton. The house was later enlarged to the size you see today.
620 North State Street	Neo-classical with Queen Anne influences. Simple massing but variety of window types and groupings. Classical detailing in Doric columns, corner pilasters and gable scrollwork. Stained and leaded glass windows and oak woodwork through out. Built in 1906 for wealthy farmer Albert T. England.
619 North State Street	Queen Anne with neo-classic details. Irregular massing more evident before roof modifications.  Original hip roof replaced by nested half-timber gables.  Large window groupings, with original leaded and stained glass.  Stair turret.  Pediment over entrance.  Dentil trim.  Stone porch piers topped by paired Doric columns.  Built-in oak sideboard in dining room with four large oak pocket doors separating dining from living room.  Original marble sinks in bathrooms and upstairs bedrooms.  Ice door on back porch.  Master bedroom still contains a mouthpiece for calls to the kitchen?an early intercom system!  Built in 1903 for John Kirby, who amassed nearly 1500 acres of farmland before his death in 1919.  The family generously established a trust fund for the current John & Mary Kirby Hospital.
612 North State Street	Neo-Georgian with English Tudor influences. Formal symmetrical facade with single repetitive window type. Half-timber gables, wide eaves, dormers, sun porches and carriage house all indicate Tudor influence. Built in 1908 for W. H. and Nell Kirby England by her father as a wedding gift. Home features ballroom in basement. A walk-through tunnel connects the house and the carriage house. Furnace was located in carriage house with piping running through the tunnel to the house. Upon Nell England's death in 1950, her entire estate was bequeathed to John & Mary Kirby Hospital, named in honor of her parents. Once again a private residence.