Federal Way, WA to Medical Lake, WA is 273.6 miles and takes about 5h 12m via I 90 and State Route 18, with a fuel budget near $61 and enough daylight to finish in a day. This trip stays within Washington state, beginning in the Pacific Coast region and ending in the same area. Given its profile, expect mostly highway driving, making it a straightforward trip. You'll cover over 270 miles, so plan for a solid block of time behind the wheel. It's a good option if you're looking for an efficient way to get across a significant portion of the state.
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
136.8 miles from Federal Way, WA
A natural place for your longest stop of the day
, about 2h 38m into the drive
.
Main Roads
Road
Distance
Duration
I 90
237.6 mi
4h 17m
State Route 18
24.4 mi
31m
West Salnave Road
4.3 mi
7m
South Peasley Canyon Road
1.8 mi
3m
South 320th Street
1.4 mi
3m
South Lefevre Street
1.1 mi
2m
State Route 902
0.8 mi
1m
Pacific Highway South
0.5 mi
1m
Longest stretch:
I 90
— 237.6 mi, about 4h 17m
Traffic on I-90
Hour-of-day weekday pattern from 47 FHWA count stations on your route.
Peak
2 PM
~978 veh/hr typical
· worst 1,681
Quietest
2 AM
~83 veh/hr
Peak-to-quiet ratio
11.8×
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 Federal Way, WA and Medical Lake, WA.
1
Start on this road
24 ft·7 sec·this road
2
Turn left onto South 312th Street
158 ft·5 sec·South 312th Street
3
Turn left onto WA 99
0.5 mi·1 min·Pacific Highway South
4
Turn left onto South 320th Street
1.4 mi·3 min·South 320th Street
Use the straight lane.
5
Continue on South Peasley Canyon Road
1.0 mi·1 min·South Peasley Canyon Road
6
Enter roundabout onto South Peasley Canyon Road
95 ft·1 sec·South Peasley Canyon Road
7
Continue on South Peasley Canyon Road
0.7 mi·1 min·South Peasley Canyon Road
8
Turn left onto West Valley Highway North
334 ft·10 sec·West Valley Highway North
Use the left lane.
9
Take the ramp
0.2 mi·28 sec
Toward WA 18 East, WA 167 North: Renton, North BendUse the right lane.
10
Keep slight left at fork
0.2 mi·30 sec
Toward WA 18 East
11
Merge onto WA 18
24 mi·31 min·State Route 18
Use the straight / slight right lanes.
12
Continue on WA 18
0.1 mi·8 sec·Snoqualmie Parkway
13
Take the exit
0.6 mi·1 min
Toward I 90 East: Spokane
14
Merge onto I 90
238 mi·4 hr 17 min·I 90
Use the straight / slight right lanes.
15
Take the exit
0.4 mi·51 sec
Toward SR 902 East: Cheney, Medical Lake
16
Turn left onto WA 902
4.3 mi·7 min·West Salnave Road
17
Continue on WA 902
0.8 mi·1 min·State Route 902
18
Continue on WA 902
1.1 mi·2 min·South Lefevre Street
19
Turn right onto East Lake Street
125 ft·4 sec·East Lake Street
20
Arrive at destination
East Lake Street
Trip Plan
To make the most of this 5-hour drive, consider an early morning departure to avoid potential traffic congestion around the Seattle metropolitan area. With a single stop suggested, you can plan to refuel and stretch your legs midway through your journey. The longest stretch on I 90 is nearly 240 miles, so ensure you have entertainment or audiobooks ready. Keep an eye on your fuel gauge, especially as you get closer to Medical Lake, as services might become less frequent on the final surface road segments. This route is designed to be completed in one day, offering flexibility in your schedule.
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 136.8 miles from Federal Way, WA, or about 2h 38m into the drive.
The longest continuous stretch on this route runs about 237.6 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 60 miles or 1h 14m in
Use this first pause for coffee, a restroom break, and a quick traffic check ahead.
Halfway reset
Around 136.8 miles or 2h 38m in
This is the best place for your longest stop, a real meal, and a full fuel check.
Final approach
Final hour starts around 4h 12m
Traffic, exits, and arrival timing usually matter more near Medical Lake, WA than in the middle of the route.
Before You Leave
+
Open the route before leaving Federal Way, WA 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 Federal Way, WA
This is one driving day of about 273.6 miles and 5h 12m.
Your first comfortable stop window is around 60 miles from Federal Way, WA.
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 I 90 for about 237.6 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 and 4.3 — GPS handles the exact turns, but know they're coming. Your lane choice matters more than the turn itself.
5
0 mi into trip|~0m in|South 312th Street
Turn left onto South 312th Street
Navigation decision point
5
3.7 mi into trip|~7m in|West Valley Highway North
Turn left onto West Valley Highway North
Lane positioning matters here
Use the left lane.
8
3.8 mi into trip|~8m in
Take the ramp toward WA 18 East, WA 167 North: Renton, North Bend
Lane positioning matters here. Multiple destination signs - pick the right one
Use the right lane.
Toward WA 18 East, WA 167 North: Renton, North...
6
4 mi into trip|~8m in
Keep slight left at fork toward WA 18 East
Highway fork - watch signs carefully
Toward WA 18 East
5
4.3 mi into trip|~9m in|WA 18 / State Route 18
Merge onto WA 18 / State Route 18
Merge point - match speed before joining. Lane positioning matters here
Use the straight / slight right lanes.
Fuel & Cost
Regular Gas
$53.30 one way
$106.60 round trip
$4.95/gal25.4 MPG avg96 kg CO2
Fuel Type
$/gal
One Way
Round Trip
midgrade
$5.18
$55.84
$111.68
premium
$5.39
$58.07
$116.14
diesel
$4.80
$51.66
$103.32
No toll roads detected on this route.
Estimated Trip Cost (one way, 1 person)
Fuel
$53
Meals
$25–$50
Total
$78–$103
Rough estimate based on US averages. Hotel $80–$140/night, meals $25–$50/day.
Estimated CO2 emission: 95.7 kg one way.
Prices: EIA weekly data, 2026-07-13.
Driving Electric?
About $29 in charging
· 1 stop
· 67% less CO2
Vehicle Type
kWh
Stops
DC Fast
Home Charge
Average EV
82.1
1
$28.73
$13.13
Efficient EV
68.4
0
$23.94
$10.94
EV Truck/SUV
109.4
1
$38.30
$17.51
Gas CO2
96 kg
EV CO2
32 kg (67% less)
Plan for 1 charging stop. A 30-minute DC fast charge mid-route should be enough to complete the trip comfortably.
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 Jul 18, 2026
Origin
Federal Way, WA
Morning
in Federal Way on Sunday
Local time
11:54 AM
PDT
Current temp
54°F
Partly Cloudy
W 5 mph0% chanceLive forecast
Red Flag Warning
Red Flag Warning issued July 17 at 9:08PM PDT until July 18 at 9:00PM PDT by NWS Spokane WA
Red Flag Warning
Red Flag Warning issued July 17 at 9:08PM PDT until July 18 at 9:00PM PDT by NWS Spokane WA
Destination
Medical Lake, WA
Morning
in Medical Lake on Sunday
Local time
11:54 AM
PDT
Current temp
58°F
Patchy Smoke
S 7 mph0% chanceLive forecast
Red Flag Warning
Red Flag Warning issued July 17 at 9:08PM PDT until July 18 at 9:00PM PDT by NWS Spokane WA
Red Flag Warning
Red Flag Warning issued July 17 at 9:08PM PDT until July 18 at 9:00PM PDT by NWS Spokane WA
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
4 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
5h 12m 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.
National Parks Near This Route
Worth a detour if your schedule allows.
Klondike Gold Rush - Seattle Unit National Historical Park
National Historical Park
Seattle flourished during and after the Klondike Gold Rush. Merchants supplied people from around the world passing through this port city on their way to a remarkable adventure in the Yukon Territory...
Park data from the National Park Service API. Alerts update every 2 hours.
More Details
What kind of drive is this?
This drive is predominantly on highways, with 96% of the route utilizing them. You'll experience a long stretch of I 90 for 237.6 miles. The transition to surface roads happens near the end of your trip, with West Salnave Road being one of the final segments. Expect to encounter dense traffic merging and exiting as you navigate through populated areas before reaching more open highway cruising.
96% highway — fuel and pacing are the main things to plan.
20 navigation steps total — most of the decisions cluster near the start and finish.
Longest single stretch: 237.6 mi on I 90.
How Hard Is This Drive?
5/10
This is a straightforward highway drive that stays mostly on I 90 and State Route 18. You will hit about 12 points where you need to pay attention to lane position or signs. The trickiest moment comes early in the drive near South 312th 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 273.6 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: near the start (South 312th Street): Navigation decision point; at 3.7 miles (West Valley Highway North): Lane positioning matters here; at 3.8 miles: Lane positioning matters here. Multiple destination signs - pick the right one.
Federal Way is a city in King County on the Puget Sound of Washington State. It is the home of the Pacific Bonsai Museum and Rhododendron Species Botanical Gardens. With a population of 96,000 (2016), Federal Way is one of Seattle's largest suburbs.
Top landmarks
•Wild Waves Theme Park — amusement park and water park in Federal Way, Washington, United States
Doable as a same-day drive at 5h 12m. Total distance: 273.6 miles.
Family Friendly
Moderate complexity with 1 natural rest stops along the way.
Solo Traveler
5h 12m drive, comfortable solo distance.
First-Time Driver
Mostly highway driving (96%). Some complex stretches to watch for.
Frequently Asked Questions
The longest stretch is about 237.6 miles on I 90. The full list of main roads is in the Roads section above.
Yes — we found about 19 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.
Only with planning. This is a long drive for kids — consider splitting it into two days rather than pushing through. Plan at least 1 meaningful breaks. There are 19 rest areas along the route for bathroom stops.
The main spots that need attention: near the start (South 312th Street): Navigation decision point; at 3.7 miles (West Valley Highway North): Lane positioning matters here; at 3.8 miles: Lane positioning matters here. Multiple destination signs - pick the right one.
Yes — Klondike Gold Rush - Seattle Unit National Historical Park. See the National Parks section for detour distances and tips on detours.
Not recommended in a single day. At 5.2 hours each way, a round trip means 10.4 hours of driving — that is an unsafe level of fatigue for most drivers. Plan at least one night at Medical Lake, WA before the return drive.
