Both lakes sit along Highway 20 in the North Cascades, but they deliver very different trips. Diablo Lake is the easy, high-impact day trip. Ross Lake is the commit-to-it backcountry lake.
Quick decision guide
Choose Diablo Lake if you want:
- Maximum scenery with minimal logistics (viewpoints, short hikes, quick paddles)
- A reliable day trip base off Highway 20
- Clear “wow” factor photos with short time investment
Choose Ross Lake if you want:
- Boat-in camping and long paddles with fewer people
- A multi-day trip feel (remote shoreline, big-lake travel)
- A true backcountry logistics experience (permits, wind planning)
The real differences that matter
1) Access and effort
Diablo Lake
- Directly along Highway 20 with multiple easy stops and trailheads nearby (for example, Thunder Knob access via Colonial Creek area).
Ross Lake
- Access is more involved. NPS notes the only vehicle access is at Hozomeen (via a long gravel road from Hope, BC), and many visitors reach Ross by boating across Diablo then portaging gear to Ross.
- If you’re staying at Ross Lake Resort, there is a Diablo/Seattle City Light ferry service and reservations are required.
Bottom line: Diablo is “show up.” Ross is “plan it.”
2) Best use case
Diablo Lake is best for
- Day trips, short paddles, quick scenic hikes
- Families and first-timers who want high reward, low risk
- People traveling through the corridor and stacking multiple stops
Ross Lake is best for
- Multi-day paddling and boat-in camping
- Groups that want quieter water access away from the road corridor
- People comfortable with big-lake wind and route planning
NPS specifically warns Ross Lake can be very windy, which should drive your plan and gear choices.
3) Camping options
Diablo Lake
- Better as a base for nearby frontcountry campgrounds and day exploration.
Ross Lake
- Designed for boat-in camping: NPS lists boat-in camps around Ross Lake and requires a backcountry permit for overnight camping.
- NPS notes Ross Lake boat-in campsites have core facilities like fire rings, picnic tables, vault toilets, and bear-resistant food storage boxes, with some docks.
- Reservation details and availability can route through Recreation.gov (NPS references Ross Lake boat-in sites and reservations).
Bottom line: If “camp on the lake” is the goal, Ross is the clear winner.
4) Time, crowds, and parking
Diablo Lake
- More roadside access means more crowd pressure and parking constraints in peak season. The upside is you can pivot quickly to another stop.
Ross Lake
- Fewer casual visitors, but you pay for that with travel time and logistics. A “simple change of plans” can be expensive once you’ve committed.
Suggested trip formats
If you have 2–4 hours
Pick Diablo Lake: viewpoint stops + a short hike (Thunder Knob is a common choice for moderate effort with views).
If you have a full day
Still Diablo unless you already have Ross logistics dialed. Diablo lets you stack: scenic stops + hike + paddle without a permit workflow.
If you have 2–3 days and want water-based backcountry
Pick Ross Lake: boat-in camping with permits and wind-aware route planning.
Practical cautions
Wind and exposure (Ross Lake)
Treat Ross like a big, wind-prone lake. Build your itinerary around morning travel windows and have a “stay put” day available.
Permits (Ross Lake)
If you’re camping on Ross, plan on a backcountry permit requirement.
Summary
- Best scenic day trip: Diablo Lake
- Best for paddling + boat-in camping: Ross Lake
- Lowest planning burden: Diablo Lake
- Most “remote” payoff: Ross Lake