Millersylvania State Park, Deep Lake
Lake · Washington
ℹ️ Community-reported spot. Details below are compiled from public sources and are reported to be accurate — always verify locally before visiting.
About this swimming hole
A state park on Deep Lake near Tumwater with two swim beaches, forested trails and a historic lodge. It's one of the South Sound's most complete lake parks, easy to reach from Olympia on a hot afternoon.
Good to know
| Water type | Lake |
|---|---|
| Water temperature | 70-75 in summer |
| Best season | June-September |
| Fees | Discover Pass |
| Reservations required | No |
| Hours | 8am-dusk |
| Parking | day-use lots |
| Amenities | restrooms, picnic tables, campground |
| County | Thurston County |
| Nearest town | Tumwater |
| Safety notes | no lifeguard; check for algae advisories |
Map
Nearby swimming holes
Frequently asked questions
Does Millersylvania State Park, Deep Lake require reservations?
No reservations are required at Millersylvania State Park, Deep Lake based on current information — but verify before you go.
Is there a fee to visit Millersylvania State Park, Deep Lake?
Reported fee info: Discover Pass. Fees can change — confirm with the official link.
When is the best time to visit Millersylvania State Park, Deep Lake?
The best season is typically June-September.
⚠️ Verify before you go. Conditions, fees, reservations, and access can change — confirm details with the official link before visiting. Last verified: September 2026