The hamlet was once known as Fayette. It is situated on Guilford Creek fed mainly from Guilford Pond which was once called Cable Pond and today is know as Guilford Lake. In the 1800's the O & W Railroad ran through it. The hamlet contained three churches, one district school, one hotel, three general stores, one hardware store, one newspaper office (The Guilford Wave), one grist mill, one saw and feed mill, a shingle and planing mill, a furniture and cheese-box manufactory, a foundry and machine shop, three blacksmith shops, one wagon shop, a butter-tub manufactory, two harness shops and a population of about 300.

William Gilbert, father of Rufus Gilbert who originated the elevated railway in NYC, opened a store in 1836. Eastman, Spaulding & Co, locally known as the East India Co. were early and prominent merchants. K. Eugene Bunnell, hardware merchant started a dry goods business in 1869 and designed the "iron-clad milk pan" which was patented.

The post-office was established in 1838 and Erastus Dickinson was the first postmaster. The first physician was Dr. John Clark who moved to Guilford in 1833.

The Guilford Iron works was established in 1845 by Andrew Bradbury and Niram Merchant. Andrew Merchant invented the Merchant waterwheel which was used on Guilford Creek

In 1839 the Guilford Mills,for flour and grist, was built and owned by Charles Windsor and W.O.Nash.

The first organ made west of the North River was constructed around 1819 by Elsworth Phelps at the age of 16

The hotel was in 1879 owned by C.M.Feek. It was the building that was first the site of the tavern by one of the first settlers of Guilford, John Dibble in 1798.

The first settler was Eli Pace who came in 1792 and built a fur trading post. In the 1800's it contained three churches, one district school, one hotel, four stores, one grist mill and saw mill, one harness shop, two blacksmith shops, one carriage and hearse manufactory (G. Graves proprietor), one undertaking establishment, one shoe shop, three copper shops, one jeweler's shop, one tailor shop and a population of 300.

The first merchants were George Fenno and John Saxton who opened a store in 1820. The first postmaster was John Saxton and the first physician was John Mather in 1827. The Bordens opened their milk plant in 1896. George Romer was the first superintendent. The nationally known race horse Lady Upton was born here in 1864 and was named Kitty. She died in 1907 and a tombstone marker over here grave is located on town road property. She raced for 13 years and her driver was George Cornell.

The first school was built by John Saxton in 1798 and in 1868 a two room school house was built on the site of the first log cabin school. In 1870 the railroad came to Mt. Upton as the branch of the Midland and Oswego.

Guilford Center which is situated on Guilford Creek, one and one-half miles below Guilford. It was once the seat of a flourishing academy which began in 1827. It contained two churches, one district school, a grocery store, one harness shop, a blacksmith shop, a tailor shop and a population of 61 in 1800's.

A hotel -the Angel Inn- was also located here and was a stage coach stop with a wooden angel above the building. The first merchants were Caleb Mann and Henry Smith who sold goods in the tavern of the hotel about 1809. The first postmaster was Dr. Colby Knapp who was also the first physician. The first lawyer was Daniel S. Dickinson. He was later elected NY Senator in 1836.

The Guilford Center Depot and Feed Store were built around the time the O & W Railroad started operation in 1866. The depot was called "Parker".

Rockdale, four miles south of Mt. Upton, was settled very early. The first settlers were James and Rubus Phelps. To build their cabins and wells they had to blast the underlining rock ledge 12 feet down and hence the name of the hamlet. A bridge was built across the river in 1799 which was the first bridge across the Unadilla River.

In the 1800's it contained one church(Union), one district school, one hotel , a saw and grist mill, one store, a creamery, a carriage shop, and a blacksmith shop, two shoe shops, and a population of 80.

The first merchant was Gaius Boughton in 1814. The first postmaster was Isaac Cox who was appointed in 1829. The first physician was James Secor who came from Mt.Upton in 1847.

The saw and grist mill was built in 1809 by Samuel Cotton and Joseph Gilbert. The Rockdale Creamery was built in the spring of 1865. The Rockdale Religious Society was organized in 1859.

The hamlet is located on the south-east corner of the town and was the junction of the New Berlin branch of the O & W railroad. So, it was once called New Berlin Junction. Joseph Gilbert in his letter of 1812, tells of stopping at "Indian Orchard". It was also called Shaver's Corners.

It is believed that the first settlers of the town of Guilford were two Frenchmen by the name of Mercereau and they settled at the mouth of Guilford Creek in East Guilford. The falls which are still present today offered a source of water power and the first mill was built their in 1789. There was a large Indian village by the bridge where the Marchers settled.

In the 1800's the hamlet contained one church (Presbyterian), a district school, a hotel, one store, a saw and grist mill, a shingle factory, a cider mill, a shoe shop, two blacksmith shops, a carriage repair shop and a population of about 75.

The chief industry of the hamlet were four quarries of flagging stone. A large mill was built by the falls in 1806. It was referred to as Lascade Mills then owned by the Preston brothers. Where the bridge crossed are rare white barked sycamore trees along the banks of the brook. It is believed that this is the only native stand of sycamores in the whole Unadilla River watershed.

Rockwells Mills is the name of a post-office and station of the O & W Railroad about a mile north of Mt. Upton. The name comes from the mills of Chester W. Rockwell which was located there. The settlements of Rockwells Mills and Latham Corners were less than a half mile apart so is treated to some extent as one. The first settlers were Sullivan Reynolds, Robert Mcleod, Lemuel Cornell, John Secor and James Hayes. All came in 1791. Reynolds built a gristmill on the east side of the river.

The hamlet was also called "Union" until 1895 when Urastus Rockwell bought the large mill. Howard Rockwell was the first postmaster in 1874 when the railroad came through.

The mill was burned in 1870 and rebuilt under the name of C.W.Rockwell & Co. The woolen mill was made partly of stone and partly of wood. Part remains today as "The Old Mill Restaurant. Between Rockwells Mills and Latham Corners was a Methodist church whose history dates back to the inception of Methodism in this part of the country.