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zipcodes.pro — ZIP/21710

21710

ZIP 21710 is Adamstown, Maryland, in Frederick County; area codes 240 and 301; Eastern time.

Type
Standard
Time zone
America/New_York
County
Frederick
Population
4,661
Coordinates
39.3079, -77.4321
☼ Live from 21710 — Adamstown, MD

Weather right now

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Local time: —

Where 21710 is

Approximate ZIP boundary (Census ZCTA 2020). ZIP codes are mail routes, not areas, so the shape shown is the Census tabulation area that approximates it.

★ Weird and wonderful facts about 21710
  • 🔢 Type 21710 into a pocket calculator and turn it upside down: OILIZ — not quite a word, sorry.
  • ➕ As a number, 21,710 = 2 × 5 × 13 × 167. Its digits add up to 11, a total 714 other ZIP codes share.
  • 💾In binary, the way a computer stores it: 101010011001110
  • 🏠 Its numerical neighbours: 21709 (Frederick, MD, 11 mi away) and 21711 (Big Pool, MD, 40 mi away).
  • 🔄 Backwards, 21710 becomes 01712, which is not a ZIP code at all.
  • 👥 40 other ZIP codes are made of exactly the same digits (01721, 02117, 02171, 07112, 10172, 10271, …). The farthest-flung twin is 71102 in Shreveport, LA, 1,021 miles away.
  • 🧭 Farther north than 51% of all ZIP codes, and farther east than 80%.
  • 🎯1,124 miles east of the geographic center of the Lower 48, near Lebanon, Kansas.
  • 🌏 Dig straight through the Earth from 21710 and you would come out at 39.31°S, 102.57°E — 902 miles from Perth, Australia, the nearest big city to that spot.
  • ☀Longest day of the year: 14h 56m of daylight. Shortest: 9h 24m.
  • 📏 At 29.4 square miles of land, 21710 is bigger than 45% of ZIP codes — room for about 22 Central Parks.
🌙 The sky over 21710 today
  • Working out the sun…
🌋 Shake report
  • Checking the USGS…

Source: USGS.

People and housing

Population4,661This ZIP4,661
Households1,672This ZIP1,672
Housing units1,773This ZIP1,773
Median age51.9This ZIP51.9Maryland39.4US 38.9
Median household income$163,864This ZIP$163,864Maryland$103,678US $80,734
Median home value$591,100This ZIP$591,100Maryland$419,900US $332,700
Median gross rent$2,381This ZIP$2,381Maryland$1,705US $1,413
Bachelor's degree or higher53.1%This ZIP53.1%
Mean commute34.3 minThis ZIP34.3 min
Population density158.6 / sq miThis ZIP158.6 / sq mi

Business and tax activity

Business establishments55This ZIP55
Employees524This ZIP524
Annual payroll$30,353,000This ZIP$30,353,000
Tax returns filed2,250This ZIP2,250
Total adjusted gross income$279,952,000This ZIP$279,952,000

Land area

Land area29.38 sq miThis ZIP29.38 sq mi
Water area0.46 sq miThis ZIP0.46 sq mi

Other place names in 21710

Census places whose land this ZIP code overlaps. The Postal Service may accept other city names in an address, too.

ZIP codes near 21710

ZIPCityDistance
21717 Buckeystown, MD 2.1 mi
21704 Frederick, MD 4.4 mi
21703 Frederick, MD 4.6 mi
21790 Tuscarora, MD 4.9 mi
21777 Point Of Rocks, MD 5.5 mi
21754 Ijamsville, MD 6.4 mi
20838 Barnesville, MD 6.7 mi
21705 Frederick, MD 7.1 mi
20842 Dickerson, MD 7.5 mi
21755 Jefferson, MD 8.1 mi

Find every ZIP code within 10 miles of 21710 →

Questions about this ZIP code

Where is ZIP code 21710?

21710 is in Adamstown, Maryland, in Frederick County, part of the Washington-Arlington-Alexandria, DC-VA-MD-WV metropolitan area. Its published point location is 39.3079, -77.4321.

What county is 21710 in?

21710 lies in Frederick County.

What area code is 21710?

Adamstown uses area codes 240 and 301, from NANPA's telephone records.

What time zone is 21710 in?

21710 uses America/New_York.

How many people live in 21710?

About 4,661 people live in ZIP code 21710, in 1,672 households, at 158.6 people per square mile. These are American Community Survey 5-year estimates for the ZIP Code Tabulation Area, not a headcount.

What is the median household income in 21710?

$163,864 a year, against $103,678 across Maryland.

What ZIP codes are near 21710?

The closest are 21717 (2.1 mi), 21704 (4.4 mi), 21703 (4.6 mi), 21790 (4.9 mi) and 21777 (5.5 mi).

Is 21710 a PO Box ZIP code?

21710 is a standard ZIP code. A normal ZIP code with street delivery.

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zipcodes.pro. “21710 ZIP Code — Adamstown, Maryland (Frederick County).” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/zip/21710

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