South Bel Air, MD to Gaithersburg, MD is 69.5 miles and takes about 1h 31m via Intercounty Connector, I-95, and Harbor Tunnel Thruway, with a fuel budget near $12 and enough daylight to finish in a day. This trip stays within Maryland's Northeast region, offering a direct path between two points. Expect a route that involves frequent turns and navigating local roads, rather than a purely highway experience. It's a manageable drive, perfect for a single day trip without feeling rushed.
Trip Pace
Same-day drive is realistic
A same-day return is realistic if you keep stops short.
Midpoint
34.8 miles from South Bel Air, MD
A natural place for your longest stop of the day
, about 47m into the drive
.
Main Roads
Road
Distance
Duration
Intercounty Connector
15.7 mi
19m
I 95
13.6 mi
15m
Harbor Tunnel Thruway
12 mi
15m
John F. Kennedy Memorial Highway
8.1 mi
9m
Express Toll Lanes
7.7 mi
9m
Vietnam Veterans Memorial Highway
3.9 mi
5m
South Frederick Avenue
1.6 mi
3m
Baltimore Harbor Tunnel
1.4 mi
2m
Longest stretch:
Intercounty Connector
— 15.7 mi, about 19m
Turn-by-Turn Driving Directions
Step-by-step road directions between South Bel Air, MD and Gaithersburg, MD.
1
Start on South Shamrock Road
0.3 mi·1 min·South Shamrock Road
2
At end of road, turn right onto East MacPhail Road
0.3 mi·44 sec·East MacPhail Road
3
Turn left onto MD 924
496 ft·14 sec·South Main Street
4
Continue on MD 924
0.6 mi·1 min·Emmorton Road
5
Turn right onto West Ring Factory Road
0.6 mi·1 min·West Ring Factory Road
6
Turn left onto MD 24
3.9 mi·5 min·Vietnam Veterans Memorial Highway
Use the left lane.
7
Take the exit
0.6 mi·1 min
Toward I 95 South: BaltimoreUse the straight / slight right lanes.
8
Merge onto I 95
8.1 mi·9 min·John F. Kennedy Memorial Highway
Use the straight / slight right lanes.
9
Keep slight left at fork onto Express Toll Lanes
6.5 mi·7 min·Express Toll Lanes
Use the slight left lane.
10
Keep slight left at fork onto Express Toll Lanes
1.2 mi·1 min·Express Toll Lanes
Use the slight left lane.
11
Merge onto I 895
3.8 mi·5 min·Harbor Tunnel Thruway
12
Continue on I 895
1.4 mi·2 min·Baltimore Harbor Tunnel
13
Continue on I 895
2.2 mi·3 min·Harbor Tunnel Thruway
Use the straight / slight right lanes.
14
Continue on I 895
0.5 mi·39 sec·Harbor Tunnel Throughway
15
Keep slight left at fork onto I 895
0.5 mi·41 sec·Harbor Tunnel Throughway
Use the straight / slight right lanes.
16
Continue on I 895
6.0 mi·7 min·Harbor Tunnel Thruway
Use the straight / right lanes.
17
Merge onto I 95
14 mi·15 min·I 95
Use the straight / slight right lanes.
18
Take the exit
0.9 mi·1 min
Exit 31BToward MD 200 Toll WestUse the straight / slight right lanes.
19
Merge onto MD 200 Toll
9.5 mi·11 min·Intercounty Connector
Use the straight / slight right lanes.
20
Continue on MD 200 Toll
6.2 mi·7 min·Intercounty Connector
Exit 8A
21
Continue on I 370
0.5 mi·41 sec·I 370
22
Take the exit
0.4 mi·46 sec
Exit 2Toward MD 355: Rockville, GaithersburgUse the slight right lane.
23
Turn right onto MD 355
0.2 mi·27 sec·Frederick Road
24
Continue on MD 355
1.6 mi·3 min·South Frederick Avenue
25
Turn left
85 ft·6 sec
26
Arrive at destination
Trip Plan
Given the relatively short 1h 31m duration, this trip offers a lot of flexibility. Aiming to depart mid-morning could help you avoid the heaviest commuter traffic. While there are no mandatory stops suggested, plan for brief breaks as needed, especially considering the turn-heavy nature of the drive. Keep an eye on your fuel level; with a $12 estimated cost, it's wise to fill up before you leave South Bel Air or at one of the many service areas along I-95 if you see your gauge getting low.
Morning Departure
Leave by 9 AM and you'll arrive before lunch.
Evening Departure
Even a 4 PM departure gets you there before dark in summer.
You can normally do this drive in one day.
You may only need one short stretch break if traffic stays light.
The halfway point lands around 34.8 miles from South Bel Air, MD, or about 47m into the drive.
The longest continuous stretch on this route runs about 15.7 miles.
This is a comfortable same-day trip.
Departure
Before you leave
Start with fuel, water, and navigation already sorted so the first hour feels easy.
First stop
Around 15 miles or 21m in
Use this first pause for coffee, a restroom break, and a quick traffic check ahead.
Halfway reset
Around 34.8 miles or 47m in
This is the best place for your longest stop, a real meal, and a full fuel check.
Final approach
Final hour starts around 1h 16m
Traffic, exits, and arrival timing usually matter more near Gaithersburg, MD than in the middle of the route.
Before You Leave
+
Open the route before leaving South Bel Air, MD so your first major turns are already loaded.
Day 1
Settle into the route from South Bel Air, MD
This is one driving day of about 69.5 miles and 1h 31m.
Your first comfortable stop window is around 15 miles from South Bel Air, MD.
This route can stay practical as a one-day drive if traffic stays reasonable.
The longest stretch is on Intercounty Connector for about 15.7 miles.
Where to Stop
Rest stops, refuel points, and overnight suggestions along this route.
Place data sourced from public business listings. Hours and availability may vary.
Heads-up: tricky spots
5 of 15
5 decision points cluster between mile 5.8 and 67.3 — GPS handles the exact turns, but know they're coming. Your lane choice matters more than the turn itself.
6
5.8 mi into trip|~10m in
Take the exit toward I 95 South: Baltimore
Exit ramp - move to the correct lane early. Lane positioning matters here
Use the straight / slight right lanes.
Toward I 95 South: Baltimore
6
14.6 mi into trip|~21m in|Express Toll Lanes
Keep slight left at fork onto Express Toll Lanes
Highway fork - watch signs carefully. Lane positioning matters here
Use the slight left lane.
6
21 mi into trip|~29m in|Express Toll Lanes
Keep slight left at fork onto Express Toll Lanes
Highway fork - watch signs carefully. Lane positioning matters here
Use the slight left lane.
7
50.2 mi into trip|~1h 5m in
Take the exit toward MD 200 Toll West
Exit ramp - move to the correct lane early. Lane positioning matters here
Use the straight / slight right lanes.
Exit 31B
Toward MD 200 Toll West
8
67.3 mi into trip|~1h 27m in
Take the exit toward MD 355: Rockville, Gaithersburg
Exit ramp - move to the correct lane early. Lane positioning matters here. Multiple destination signs - pick the right one
Use the slight right lane.
Exit 2
Toward MD 355: Rockville, Gaithersburg
Fuel & Cost
Regular Gas
$11.52 one way
$23.04 round trip
$4.21/gal25.4 MPG avg24 kg CO2
Fuel Type
$/gal
One Way
Round Trip
midgrade
$4.61
$12.62
$25.24
premium
$4.93
$13.48
$26.96
diesel
$5.61
$15.34
$30.69
Estimated Tolls: $0.84
Harbor Tunnel Thruway
(12 mi)$0.84
Toll estimates based on average 2024-2025 rates. EZ-Pass/SunPass discounts may lower the actual cost.
Estimated Trip Cost (one way, 1 person)
Fuel
$12
Tolls
$1
Meals
$25–$50
Total
$37–$62
Rough estimate based on US averages. Hotel $80–$140/night, meals $25–$50/day.
Estimated CO2 emission: 24.3 kg one way.
Prices: EIA weekly data, 2026-04-13.
Driving Electric?
About $7 in charging
· 0 stops
· 67% less CO2
Vehicle Type
kWh
Stops
DC Fast
Home Charge
Average EV
20.8
0
$7.30
$3.34
Efficient EV
17.4
0
$6.08
$2.78
EV Truck/SUV
27.8
0
$9.73
$4.45
Gas CO2
24 kg
EV CO2
8 kg (67% less)
This trip is well within single-charge range for most EVs. No charging stops needed if you start fully charged.
DC fast charging avg $0.35/kWh. Home charging avg $0.16/kWh. US grid CO2: 0.39 kg/kWh.
Travel Intel
Current conditions at both ends of the drive.
Forecast as of Apr 18, 2026
Origin
South Bel Air, MD
Late night
in South Bel Air on Sunday
Local time
5:54 AM
EDT
Current temp
73°F
Mostly Sunny
SE 8 to 13 mph2% chanceLive forecast
Destination
Gaithersburg, MD
Late night
in Gaithersburg on Sunday
Local time
5:54 AM
EDT
Current temp
84°F
Mostly Sunny
SE 7 to 12 mph5% chanceLive forecast
Seasonal Notes
Summer travel usually means heavier construction, hotter rest stops, and busier weekend traffic around major cities.
Winter travel shortens daylight, so a route that looks manageable on paper can feel much longer after dark.
Holiday weekends tend to make both departure and arrival windows slower than the raw route time suggests.
Time zone
Same local time
Origin and destination are on the same clock, so arrival timing is easier to judge at a glance.
Temperature spread
11 degrees warmer at arrival
A meaningful temperature swing is a good cue to rethink layers, water, and how soon you want to arrive.
Road read
1h 31m on the road
The weather snapshot is not static. If you are leaving later, give both cities one more quick forecast check before departure.
Weather data from the National Weather Service. Conditions may change; check closer to your travel date.
National Parks Near This Route
Worth a detour if your schedule allows.
Chesapeake & Ohio Canal National Historical Park
National Historical Park
Preserving America's early transportation history, the C&O Canal began as a dream of passage to Western wealth. Operating for nearly 100 years the canal was a lifeline for communities along the Potoma...
10 mi from route
~25 min detour
$20
near mile 67.1
The Potomac River corridor is rich in both history and recreation, offering a chance to both explore your heritage and choose your adventure along the way. Start your journey here!
17 mi from route
~43 min detour
Free
near mile 69.5
During the summer of 1864, the Confederacy carried out a bold plan to turn the tide of the Civil War in their favor. They planned to capture Washington, DC and influence the election of 1864. On July...
18 mi from route
~46 min detour
Free
near mile 69.5
Park data from the National Park Service API. Alerts update every 2 hours.
More Details
What kind of drive is this?
This drive has a 'turn-heavy local drive' profile, meaning you'll be navigating more surface streets and intersections than you might expect for a 69.5-mile journey. While only 20% of the trip is on highways like I-95, the longest uninterrupted stretch you'll encounter is 15.7 miles on the Intercounty Connector. Be prepared for a dynamic driving experience that shifts between quicker highway segments and more deliberate local road travel.
Only 20% highway — the rest is turn-by-turn surface driving.
26 navigation steps total — most of the decisions cluster near the start and finish.
Longest single stretch: 15.7 mi on Intercounty Connector.
How Hard Is This Drive?
10/10
Expect a hands-on drive with frequent turns and local roads rather than long highway stretches. This route has several spots where lane changes, forks, or exits need your full attention. The trickiest moment comes around 5.8 miles in.
Driving Effort10/10
Demanding - stay alert through the decision-heavy sections
Balances navigation complexity with total wheel time.
This drive requires moderate attention. Across 69.5 miles you will encounter 15 spots where lane choice or exit timing matters. Not difficult for experienced highway drivers, but worth previewing the tricky sections before you go.
Where does it get tricky?
The main spots that need attention: at 5.8 miles: Exit ramp - move to the correct lane early. Lane positioning matters here; at 14.6 miles (Express Toll Lanes): Highway fork - watch signs carefully. Lane positioning matters here; at 21 miles (Express Toll Lanes): Highway fork - watch signs carefully. Lane positioning matters here.
Who Is This Route For?
Weekend Trip
Doable as a same-day drive at 1h 31m. Total distance: 69.5 miles.
Family Friendly
Moderate complexity with 0 natural rest stops along the way.
Solo Traveler
1h 31m drive, comfortable solo distance.
Scenic Drive
Mostly surface roads route profile with national parks nearby.
Frequently Asked Questions
The longest stretch is about 15.7 miles on Intercounty Connector. The full list of main roads is in the Roads section above.
Expect about $0.84 in tolls one way, starting with Harbor Tunnel Thruway. Most Northeast and Midwest toll agencies accept E-ZPass; in the West and Texas, transponders like TxTag or FasTrak apply. If you do not have a transponder, cashless tolling plates will mail a bill to the vehicle's registered address — usually with a surcharge, so a rental-car toll pass is often cheaper than paying by mail.
It helps. This route has a higher-than-average number of complex decision points, which get harder in the dark. If the last hour of the trip is on surface roads or mountain grades, aim to arrive at Gaithersburg, MD before sunset when you can. Check the Trip Plan for departure windows that land you in daylight.
Yes. At under 2 hours behind the wheel, this works well for families — plan one quick stop if you have younger kids.
The main spots that need attention: at 5.8 miles: Exit ramp - move to the correct lane early. Lane positioning matters here; at 14.6 miles (Express Toll Lanes): Highway fork - watch signs carefully. Lane positioning matters here; at 21 miles (Express Toll Lanes): Highway fork - watch signs carefully. Lane positioning matters here.
Yes — Chesapeake & Ohio Canal National Historical Park, Potomac Heritage National Scenic Trail and Monocacy National Battlefield. See the National Parks section for detour distances and tips on detours.
Yes. A round trip is manageable in a single day if you plan a break at Gaithersburg, MD before heading back.
