Merrillsville is located on the Port Kent and Hopkinton Turnpike (presently County Route 26, formerly County Route 99) one mile west of New York Route 3, two miles south-east of Loon Lake.

The town of Franklin was formed from the town of Belmont in 1836. The hamlet of Merrillsville appears on a map by the early 1830s and is shown on David Burr's 1839 map of Franklin County. The settlement's name was derived from the family name of Merrill. Three generations of Merrills came to this area from Vermont before the Port Kent and Hopkinton Turnpike was finished (1829-32) . It was along this route that the Merrill families settled, as well as the Gates, Lemsons, Loverins and Smiths. These names appear on the map of Township No. 10, Old Military tract, in the John Richards Survey of 1813.

The area was sparsely settled and land was cheap, which enabled the Merrill families to acquire hundreds of acres. Among the properties developed by the family was an inn that served as a stagecoach stop on the turnpike. This inn also served as the first post office in the town of Franklin, with John R. Merrill appointed postmaster in 1837. Members of the Merrill family were well educated and served in many areas of town government. The minutes of the town of Franklin board meetings between 1836 and 1907 reveal the many offices in which they served.

Source: National Register of Historic Places Registration Form for the Merrillsville Cure Cottage

Plattsburgh Sentinel,  January 8, 1869

William J. Ayers has been appointed Postmaster at Merrillsville, Franklin Co.

Beers Franklin County Atlas, 1876

Franklin Business Notices.

Littlejohn J. W., Proprietor Merrillsville Hotel, Dist. 3. P. O. Merrillsville.
Smith L. L., Proprietor Hunter's Home, Dist. 3. P. O. Merrillsville.
Cochran E. I., Farmer, Dist 8. Merrillsville.
Merrill J. D., Farmer, Dist. 8. P. O. Merrillsville.

Malone Palladium, 27 March 1879

JAS. LITTLEJOHN, of Merrillsville, received forty thousand speckled trout on Thursday evening last from the State hatching houses at Rochester, and started with them at once for Loon Lake. We understand that they were procured through the efforts and at the expense of Mr. CHASE, who is building the new hotel at that point. Mr. FULLER, at Meacham, has about one hundred and twenty-five thousand fish of his own hatching—mostly salmon—which he will place in that water this spring. He has pursued the same policy there for a number of years past, and the-result is seen in the fact that Meacham is, about the only lake in the whole wilderness where the fishing holds its own, if indeed it is not even better than it was five years ago. This course is so manifestly the wisest one for proprietors of summer resorts in the Adirondacks to adopt that we are surprised that more of them have not done so. The expense is but trifling and the benefits must prove enormous. If it be not soon generally followed and if Mr Fuller and Mr. Chase continue it, they will at no very distant time enjoy a monopoly of the sportsman's patronage. Beauty and fashion may prefer other places but; the lover of the rod and line will go where he can find employment for them.

The Merrillsville Post Office was started in 1837, with John R. Merrill as Postmaster.

The name was changed to Hunters' Home [the Paul Smith family's hotel] in 1858, was changed back to Merrillsville in 1858, and eventually became Loon Lake in 1882.