National Park Service · Maryland
Marble Quarry Hiker-Biker Campsite
National Park Service · Maryland, United States · in Chesapeake & Ohio Canal National Historical Park
- Sites
- 1
- Season
- Year-round
- Cost
- Walk-in, tent-only site: free. First come, first served
- Drinking water
- No
- Restrooms
- Yes
- Showers
- No
- Dump station
- No
- Laundry
- No
- Elevation
- 194 ft
- Dark sky
- Bortle class 4
- Cell coverage
- AT&T weak · T-Mobile none · Verizon none (carriers' 4G LTE filings to the FCC, 2025-12; not measured here)
- Lake
- Chesapeake & Ohio Canal National Historical Park
- Nearest town
- Poolesville
- Address
- Poolesville, MD, 20837
- Phone
- (301) 739-4200
About
Mile 38.2 - Hiker-biker campgrounds are located along the towpath approximately every 5-7 miles. No fee or reservation required. Overnight stays are limited to one night. All sites include a chemical toilet, picnic table, grill, and water.
Please Note: Water at hiker-biker campsites is non-potable. Water is not treated and not for drinking or cooking. If you use this water, you are advised to filter, chemically treat, or boil before use. Water is turned off from mid-November to mid-April each year.
Weather, month by month
| Month | Typical high | Typical low | Coldest night | Hottest day | Years with a night below 32°F |
|---|---|---|---|---|---|
| January | 40° | 27° | 7° | 57° | 11 of 11 |
| February | 45° | 30° | 12° | 69° | 11 of 11 |
| March | 56° | 37° | 17° | 75° | 7 of 11 |
| April | 69° | 47° | 29° | 90° | 2 of 11 |
| May | 74° | 57° | 42° | 97° | 0 of 11 |
| June | 82° | 64° | 55° | 95° | 0 of 11 |
| July | 89° | 72° | 61° | 102° | 0 of 11 |
| August | 85° | 71° | 61° | 98° | 0 of 11 |
| September | 80° | 65° | 52° | 96° | 0 of 11 |
| October | 66° | 49° | 38° | 84° | 0 of 10 |
| November | 53° | 38° | 27° | 71° | 4 of 10 |
| December | 45° | 32° | 15° | 64° | 10 of 10 |
Mid-month figures from 2016–2026 of daily weather at this spot (ERA5 reanalysis via Open-Meteo, CC BY 4.0), in °F. Typical is the median; coldest and hottest are the extremes seen.
Nearby campgrounds
- Turtle Run Hiker-Biker Campsite · National Park Service · 3 mi · 1 sites
- Indian Flats Hiker-Biker Campsite · National Park Service · 4 mi
- Chisel Branch Hiker-Biker Overnight (HBO) Campsite · National Park Service · 5 mi · 1 sites
- Calico Rocks Hiker-Biker Overnight (HBO) Campsite · National Park Service · 7 mi · 1 sites
- Bald Eagle Island Hiker-Biker Campsite · National Park Service · 9 mi · 1 sites
All public campgrounds in Maryland · Every state and province · Facts read from the operator 2026-02-25. Confirm fees, rules and current status with the operator before you go.