Erie to South Union is 239.9 miles and takes about 4h 53m via Southern Tier Expressway and US 15, with a fuel budget near $43 and enough daylight to finish in a day. This drive stays within Pennsylvania, connecting the Northeast region of the state to its southern part. With over 90% of the route on highways, expect a fairly direct and efficient trip. This is a straightforward drive, ideal if you want to cover ground quickly without many detours.
Trip Pace
Same-day drive is realistic
A same-day return is possible, but it will make for a full day on the road.
Break Rhythm
1 planned break
Plan on a short reset every 3 to 4 hours to stay fresh behind the wheel.
Midpoint
119.9 miles from Erie, PA
A natural place for your longest stop of the day
, about 2h 25m into the drive
.
Hour-of-day weekday pattern from 24 FHWA count stations on your route.
Peak
3 PM
~527 veh/hr typical
· worst 690
Quietest
2 AM
~31 veh/hr
Peak-to-quiet ratio
17×
busier at peak than in the quiet hours
12a6anoon6p11p
Averaged across 52 weeks of 2023 FHWA Travel Monitoring Analysis System data. Weekday hours only (Mon–Fri).
Turn-by-Turn Driving Directions
Step-by-step road directions between Erie, PA and South Union, PA.
1
Start on State Street
0.1 mi·35 sec·State Street
2
Turn left onto East 8th Street
1.1 mi·2 min·East 8th Street
3
Turn right onto East Bayfront Parkway
0.3 mi·44 sec·East Bayfront Parkway
4
Continue on PA 290
4.4 mi·7 min·Bayfront Connector
Use the straight / right lanes.
5
Continue on PA 290; PA 430
1.0 mi·1 min·Station Road
6
Take the exit
0.2 mi·31 sec
7
Merge onto I 90
4.1 mi·4 min·AMVETS Memorial Highway
8
Take the exit
0.5 mi·37 sec
Exit 37Toward I 86 East: Jamestown
9
Continue on I 86
7.0 mi·8 min·Hopkins-Bowser Highway
10
Continue on I 86; NY 17
168 mi·3 hr 14 min·Southern Tier Expressway
11
Take the exit onto US 15
0.2 mi·20 sec·US 15
Exit 44A-BToward I 99 South, US 15 South, NY 417: Williamsport, Gang Mills
12
Keep slight left at fork onto US 15
44 mi·49 min·US 15
Exit 44AToward I 99 South, US 15 South: Williamsport
13
Take the exit
0.5 mi·1 min
Exit 165Toward SebringUse the slight right lane.
14
Turn left onto Bloss Mountain Road
0.2 mi·17 sec·Bloss Mountain Road
15
Continue on Old Route 15
1.4 mi·1 min·Old Route 15
Use the straight lane.
16
Turn slight left onto Old Mill Road
0.4 mi·1 min·Old Mill Road
17
Turn straight onto PA 414
3.8 mi·6 min·PA 414
18
Turn right onto Salt Spring Road
1.5 mi·5 min·Salt Spring Road
19
Turn left onto T329
0.9 mi·3 min·Beck Road
20
Turn left onto South Union Road
81 ft·3 sec·South Union Road
21
Arrive at destination
South Union Road
Trip Plan
Given the 4h 53m estimated drive time, you can comfortably complete this trip in a single day. Consider leaving in the morning to maximize daylight and allow for flexibility if you encounter any unexpected delays. The longest stretch without a significant break is 168 miles, so plan your fuel and rest stops accordingly, perhaps around the halfway point. Keep an eye on your fuel gauge, especially as you approach the end of the Southern Tier Expressway, to ensure you have enough to reach your destination or a convenient refueling station.
Morning Departure
An early start around 7-8 AM gets you there with plenty of daylight left.
Evening Departure
A late afternoon start means arriving after dark. Morning is better.
You can normally do this drive in one day.
Plan roughly 1 meaningful break for fuel, food, and rest.
The halfway point lands around 119.9 miles from Erie, PA, or about 2h 25m into the drive.
The longest continuous stretch on this route runs about 168 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 53 miles or 1h 7m in
Use this first pause for coffee, a restroom break, and a quick traffic check ahead.
Halfway reset
Around 119.9 miles or 2h 25m in
This is the best place for your longest stop, a real meal, and a full fuel check.
Final approach
Final hour starts around 3h 53m
Traffic, exits, and arrival timing usually matter more near South Union, PA than in the middle of the route.
Before You Leave
+
Open the route before leaving Erie, PA so your first major turns are already loaded.
+
Leave with enough water and a charging cable within reach, not packed away.
+
Check your fuel range against the first long segment, especially if you are starting outside city service areas.
Day 1
Settle into the route from Erie, PA
This is one driving day of about 239.9 miles and 4h 53m.
Your first comfortable stop window is around 53 miles from Erie, PA.
This route can stay practical as a one-day drive if traffic stays reasonable.
Plan about 1 real break rather than only quick fuel stops.
The longest stretch is on Southern Tier Expressway for about 168 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 12
5 decision points cluster between mile 0.1 and 231.2 — GPS handles the exact turns, but know they're coming. Your lane choice matters more than the turn itself.
4
0.1 mi into trip|~0m in|East 8th Street
Turn left onto East 8th Street
Navigation decision point
5
11.3 mi into trip|~19m in
Take the exit toward I 86 East: Jamestown
Exit ramp - move to the correct lane early
Exit 37
Toward I 86 East: Jamestown
6
186.8 mi into trip|~3h 42m in|US 15
Take the exit onto US 15 toward I 99 South, US 15 South, NY 417: Williamsport, Gang Mills
Exit ramp - move to the correct lane early. Multiple destination signs - pick the right one
Exit 44A-B
Toward I 99 South, US 15 South, NY 417: William...
7
187 mi into trip|~3h 43m in|US 15
Keep slight left at fork onto US 15 toward I 99 South, US 15 South: Williamsport
Highway fork - watch signs carefully. Multiple destination signs - pick the right one
Exit 44A
Toward I 99 South, US 15 South: Williamsport
7
231.2 mi into trip|~4h 32m in
Take the exit toward Sebring
Exit ramp - move to the correct lane early. Lane positioning matters here
Use the slight right lane.
Exit 165
Toward Sebring
Fuel & Cost
Regular Gas
$42.43 one way
$84.85 round trip
$4.49/gal25.4 MPG avg84 kg CO2
Fuel Type
$/gal
One Way
Round Trip
midgrade
$4.92
$46.47
$92.94
premium
$5.24
$49.53
$99.06
diesel
$5.35
$50.53
$101.06
No toll roads detected on this route.
Estimated Trip Cost (one way, 1 person)
Fuel
$42
Meals
$25–$50
Total
$67–$92
Rough estimate based on US averages. Hotel $80–$140/night, meals $25–$50/day.
Estimated CO2 emission: 83.9 kg one way.
Prices: EIA weekly data, 2026-06-01.
Driving Electric?
About $25 in charging
· 0 stops
· 67% less CO2
Vehicle Type
kWh
Stops
DC Fast
Home Charge
Average EV
72
0
$25.19
$11.52
Efficient EV
60
0
$20.99
$9.60
EV Truck/SUV
96
1
$33.59
$15.35
Gas CO2
84 kg
EV CO2
28 kg (67% less)
Plan for 0 charging stops, roughly every 270 miles. Allow 25-40 minutes per stop at a DC fast charger.
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 Jun 3, 2026
Origin
Erie, PA
Evening
in Erie on Wednesday
Local time
8:10 PM
EDT
Current temp
55°F
Mostly Clear
SW 3 mph0% chanceLive forecast
Destination
South Union, PA
Evening
in South Union on Wednesday
Local time
8:10 PM
EDT
Current temp
46°F
Mostly Clear
N 5 mph1% chanceLive forecast
77°F
Wheeler, NY
120 mi in
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
9 degrees cooler at arrival
A meaningful temperature swing is a good cue to rethink layers, water, and how soon you want to arrive.
Road read
4h 53m on the road
An early start around 7-8 AM gets you there with plenty of daylight left.
Weather data from the National Weather Service. Conditions may change; check closer to your travel date.
More Details
What kind of drive is this?
This route is mostly highway, with 91% of the drive on high-speed roads. You'll experience a long stretch of 168 miles on the Southern Tier Expressway before transitioning to surface roads. Expect to see dense exits and merges as you navigate this primarily highway-based trip. The final portion involves US 15 and the Hopkins-Bowser Highway.
91% highway — fuel and pacing are the main things to plan.
21 navigation steps total — most of the decisions cluster near the start and finish.
Longest single stretch: 168 mi on Southern Tier Expressway.
How Hard Is This Drive?
5/10
This is a straightforward highway drive that stays mostly on Southern Tier Expressway and US 15. You will hit about 12 points where you need to pay attention to lane position or signs. The trickiest moment comes around 0.1 miles in near East 8th Street.
Driving Effort5/10
Moderate - straightforward overall, but long enough or busy enough to require pacing
Balances navigation complexity with total wheel time.
This drive requires moderate attention. Across 239.9 miles you will encounter 12 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 0.1 miles (East 8th Street): Navigation decision point; at 11.3 miles: Exit ramp - move to the correct lane early; at 186.8 miles (US 15): Exit ramp - move to the correct lane early. Multiple destination signs - pick the right one.
Elevation Profile
Gently rolling terrain
1,898 ft653 ft
Total Climb
2,300 ft
Total Descent
1,143 ft
Highest Point
1,898 ft
~137.1 mi in
Elevation Range
1,246 ft
Towns Mentioned on Route Signs
Based on OSRM destination-sign hints, not a full list of every settlement the road passes.
On the drive from Erie, PA to South Union, PA, road signs begin pointing toward Gang Mills along the way.
Doable as a same-day drive at 4h 53m. Total distance: 239.9 miles.
Family Friendly
Moderate complexity with 1 natural rest stops along the way.
Solo Traveler
4h 53m drive, comfortable solo distance.
First-Time Driver
Mostly highway driving (91%). Some complex stretches to watch for.
Frequently Asked Questions
The longest stretch is about 168 miles on Southern Tier Expressway. The full list of main roads is in the Roads section above.
Yes — we found about 15 rest areas or service plazas within a short detour of the route (from OpenStreetMap). See the Rest Stops tab under Nearby Places for locations and mile markers. Plan to stretch, use the bathroom, and top off fluids every 2–3 hours on longer drives.
Yes, with realistic expectations. Build in a stop roughly every 2 hours, have snacks and activities ready, and check the Nearby Places tabs for kid-friendly stops along the way.
The main spots that need attention: at 0.1 miles (East 8th Street): Navigation decision point; at 11.3 miles: Exit ramp - move to the correct lane early; at 186.8 miles (US 15): Exit ramp - move to the correct lane early. Multiple destination signs - pick the right one.
Possible but tiring. At 4.9 hours each way, an in-and-out day trip would put you behind the wheel for 9.8 hours — manageable with a long break at South Union, PA, but most travelers stay overnight.
