Difficult Run is a community in Fairfax County, Virginia, home to about 9,938 people across 8.4 square miles. It has no ZIP code of its own: it’s part of 20171, 22124 and 22181.
Homes sold for a median of $345 per square foot across 3 ZIP codes in the three months ending August 2026, and all of them were seller’s markets.
Mostly McNair; part is in Difficult Run
Mostly Oakton; part is in Difficult Run
Mostly Oakton; part is in Difficult Run
Each card is that ZIP code’s whole market, including any part outside Difficult Run. Seller’s market: under 4 months of supply; buyer’s market: over 6. Methodology
We’re writing up Difficult Run’s story and what everyday life there is like, for people thinking about moving in.
Are you a local agent who knows Difficult Run well? Agents who advertise here will be able to write the guide. Advertise on OfferBacked
| Nearest major airport | Washington Dulles International Airport (IAD)7 miles away |
|---|---|
| Nearest city of 250,000+ | Washington, DC17 miles away |
| Nearest city of 1 million+ | Philadelphia, PA140 miles away |
Straight-line distances from the center of Difficult Run; driving is longer.
Source: Airports from OurAirports (scheduled passenger service); city centers and populations from the U.S. Census Bureau.
Source: Members of Congress from the congress-legislators project; districts from the Census Bureau’s relationship files; governor and mayor from Wikidata.
It’s the 128th largest of 669 towns in Virginia by population.
Fairfax County grew from 18,580 residents in 1900 to 1,150,309 in 2020.
Fairfax County, 1900–2020
Source: U.S. Census Bureau decennial censuses (counties 1900–1990 from the Bureau’s historical county file).
Average highs peak around 84°F in summer, and winter lows average 23°F. About 43.5 inches of rain and melted snow fall in a typical year, with about 19 inches of snow.
Source: NOAA 1991–2020 climate normals, Vienna, VA weather station (3 miles away).
696,002 jobs at 31,931 businesses in Fairfax County. The biggest industries by employees:
Source: U.S. Census Bureau County Business Patterns 2023 (private employers; jobs counted where people work).
322 doctors and other health care providers list an office in Difficult Run’s ZIP codes.
Nearest hospitals
Providers with an office here
| Primary care doctors | 22 |
|---|---|
| Specialist doctors | 27 |
| Dentists | 53 |
| Nurse practitioners and physician assistants | 29 |
| Mental health providers | 92 |
| Physical and occupational therapists | 73 |
| Optometrists | 15 |
| Chiropractors | 11 |
| Pharmacies | 8 |
Source: Hospitals from CMS Hospital General Information (ratings are CMS overall star ratings); straight-line distances; providers from the CMS National Plan and Provider Enumeration System (NPPES), by practice address and primary specialty.
Parks (12 nearby)
Grocery stores
Pharmacies
Libraries
Museums
Theaters and performance venues
Counts are within about 2 miles of the center of town.
Source: Map data © OpenStreetMap contributors (openstreetmap.org/copyright), as mapped by volunteers; it can miss places or include closed ones.
Public schools here are run by Fairfax County Public Schools. Check each district’s attendance zones for a specific address.
| School | Grades | Students | Type | Distance |
|---|---|---|---|---|
| Coates ElementaryHerndon | Pre-K–6 | 996 | Public | 5.8 mi |
| Crossfield ElementaryHerndon | Pre-K–6 | 513 | Public | 1.8 mi |
| Flint Hill ElementaryVienna | Pre-K–6 | 614 | Public | 2.9 mi |
| Floris ElementaryHerndon | Pre-K–6 | 666 | Public | 4.9 mi |
| Fox Mill ElementaryHerndon | Pre-K–6 | 650 | Public | 3.2 mi |
| McNair ElementaryHerndon | Pre-K–2 | 520 | Public | 5.0 mi |
| Oak Hill ElementaryHerndon | Pre-K–6 | 628 | Public | 4.0 mi |
| Oakton ElementaryOakton | Pre-K–6 | 795 | Public | 2.2 mi |
| Waples Mill ElementaryOakton | Pre-K–6 | 750 | Public | 1.4 mi |
| McNair Upper ElementaryHerndon | 3–6 | 605 | Public | 5.0 mi |
| Carson MiddleHerndon | 7–8 | 1,358 | Public | 4.8 mi |
| Madison HighVienna | 9–12 | 2,090 | Public | 3.2 mi |
| Oakton HighVienna | 9–12 | 2,621 | Public | 3.3 mi |
| School | Grades | Students | Affiliation | Distance |
|---|---|---|---|---|
| Guidepost Montessori at HerndonHerndon | Pre-K–K | 28 | Nonsectarian | 5.2 mi |
| Hunter Mill Montessori SchoolOakton | Pre-K–K | 7 | Nonsectarian | 2.0 mi |
| Nysmith School for the GiftedHerndon | Pre-K–8 | 551 | Nonsectarian | 4.8 mi |
| St Mark Catholic SchoolVienna | Pre-K–8 | 356 | Roman Catholic | 2.5 mi |
| Dominion Christian SchoolOakton | K–12 | 333 | Christian (no specific denomination) | 1.0 mi |
| King Abdullah AcademyHerndon | K–12 | 913 | Nonsectarian | 5.0 mi |
Source: U.S. Department of Education, NCES: Common Core of Data (2024-2025) for public schools; Private School Universe Survey (2023-2024) for private schools. Listed by address; we don’t rate schools.
Buying or selling around Difficult Run? Tell us what you need and when. No agents advertise here yet, so we’ll keep your request for up to 30 days and send it to local agents who join. No obligation, and you choose who to work with.
Loading map…
Shares ZIP codes with McNair, Franklin Farm, Oakton, Floris, Fair Oaks, Wolf Trap, Sully Square and Reston.
Town boundaries don’t always match ZIP codes: a ZIP code can cross into neighboring towns, and a town can share a ZIP code with its neighbors. Facts describe the town itself; market figures describe whole ZIP codes.