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History · Mahopac

Mahopac’s post office opened in 1849, and 19% of its homes were built before 1940

Below: maps from 1892 on and the census since 1990.

1849first post office
0on the National Register
19%homes built before 1940
2famous people
Add an old photoShare a memory
Photo: johnaac · CC BY 3.0
Quick answers

How Mahopac began

When was Mahopac founded?

1849

The Mahopac post office opened in 1849, the earliest record of the town by name.

First census: 7,755 in 19902020 census: 8,932177 years
Founding year: the first Mahopac post office (Blevins & Helbock, CC0).The full story ↓

What stands out about Mahopac’s past

Read from the archive, the National Register and the record. The page puts what stands out first.

A history waiting to be writtenNo old photos of Mahopac are in the public archives yet. The rest are in attics and albums.On the map since 18924 editions of the USGS map, 1892 to 1981. Watch Mahopac change.Deep rootsA post office since 1849: 177 years of Mahopac.Old housesHalf of Mahopac’s homes were built before 1964.
★ What stands out · Help out

Start Mahopac’s collection

The first neighbors to add old photos shape how Mahopac’s history is told.

Decades since 1900 with photos
00s10s20s30s40s50s60s70s80s90s
0 of 10 decades. The empty ones are waiting for someone’s album.
Share a family photoSign in to add one+10
On the map

Mahopac on the map, 1892 to 1981

Every edition of the U.S. Geological Survey’s map of Mahopac. Tap a year, or press play to watch the town change.

Mahopac on the 1892 USGS mapMahopac on the 1944 USGS mapMahopac on the 1960 USGS mapMahopac on the 1981 USGS map1892Carmel sheet · 1:62,500

U.S. Geological Survey historical topographic maps (public domain), via Esri’s collection of the scans. The red ring marks the center of Mahopac.

Timeline

Mahopac, 1892 to 1960

Woven from the archive, old maps, post office records, the National Register and the people born here.

  1. 19th century
  2. 1892On the mapFirst mapped by the U.S. Geological Survey
  3. 20th century
  4. 1955Born hereJim Mees is born here
  5. 1960Born hereScott Makar is born here
The story

How Mahopac came to be

From Wikipedia’s history of Mahopac.

Read it all →

Mahopac was originally inhabited by the Wappinger people, an Algonquian tribe. The hamlet's land was part of a huge tract encompassing all of today's Putnam County patented in 1697 by Adolphus Philipse, son of a wealthy Anglo-Dutch gentryman, known as the Philipse Patent. During the French and Indian War, Wappingers throughout Putnam County traveled north to Massachusetts to fight for the British.

Text from Wikipedia, licensed CC BY-SA 4.0.

From the old history books

What they wrote about Mahopac in 1886

Passages that mention Mahopac, cut from the printed page as they were published.

The first store, and indeed the first building at the railroad statical near Lake Mahopac, was built by Mr. Ganung in 1860. upon a tract of land on the south side of the road. This tract was afterward sold in small lots at a large advance on its original cost.
History of Putnam County, New York1886Read the page →
Read the text

The first store, and indeed the first building at the railroad statical near Lake Mahopac, was built by Mr. Ganung in 1860. upon a tract of land on the south side of the road. This tract was afterward sold in small lots at a large advance on its original cost.

Text read by machine from the scan; it may contain errors.
The "Lake Mahopac Improvement Company" was incorporated March 8th, 1871, its object being "The erection of buildings and laying out and subdivisions of lands with building lots or villa plots at Lake Mahopac."
History of Putnam County, New York1886 · page 335Read the page →
Read the text

The "Lake Mahopac Improvement Company" was incorporated March 8th, 1871, its object being "The erection of buildings and laying out and subdivisions of lands with building lots or villa plots at Lake Mahopac."

Text read by machine from the scan; it may contain errors.

Scans and text from the Internet Archive. Books published in 1930 or earlier, which are in the public domain.

By decade

Mahopac, decade by decade

Today6 recent
Mahopac, NY 10541, USA - panoramio (2)2011Mahopac, NY 10541, USA - panoramio (2)Mahopac, NY 10541, USA - panoramio (1)2011Mahopac, NY 10541, USA - panoramio (1)Fallin firefighter2011Fallin firefighterBig snowfall nov 20112011Big snowfall nov 2011US Route 6 - New York2010US Route 6 - New YorkUS Route 6 - New York2005US Route 6 - New York
People over time

Mahopac, census by census

02,0004,0006,0008,00010,00020002020Peak: 8,932

Between 7,755 and 8,932 people in every census since 1990.

4 censuses, 1990–2020.

U.S. Census Bureau decennial counts, from the census table on Mahopac’s Wikipedia page.

Famous people

2 famous people were born in Mahopac

Writers, athletes, leaders and more, ranked by how widely they’re known.

See all →
J
Jim MeesAmerican set designer · b. 1955
S
Scott MakarAmerican academic and judge · b. 1960
Stories next door

History across the town line

Each neighbor’s History grade, on the same three inputs.

Carmel3 historic placesB+Somers7 historic placesB+

Questions about Mahopac’s history

What year was Mahopac founded?

The Mahopac post office opened in 1849, the earliest record of the town by name (U.S. post office records).

Memory lane

What the archives can’t tell you, neighbors can.

Town Square →
Start a conversation
Sources

Where this page comes from

Founding dates: Wikidata, Wikipedia, the U.S. post office records of Blevins & Helbock (CC0) and the Census. Homes by year built: Census ACS 2020–24. National Register of Historic Places: National Park Service (list of May 22, 2026). Old photos, postcards and papers: Wikimedia Commons, the Library of Congress and other public archives, credited on each item’s page. Maps: U.S. Geological Survey historical topographic maps (via Esri) and Sanborn fire-insurance maps (Library of Congress). History text and census tables: Wikipedia (CC BY-SA 4.0). Places that used to be: USGS Geographic Names Information System (2021). How TownRatings grades history →

From Wikimedia Commons (6), Wikipedia, Wikidata and Wikipedia for famous people, U.S. Geological Survey historical maps, U.S. Census counts (via Wikipedia) and old county and town histories (Internet Archive). Archive images are copied here with their credits and licenses, shown on each photo’s page. Refreshed monthly.