| Mason Lake | |
| Pushpin Map: | Washington#United States |
| Location: | King County, Washington, US, near Snoqualmie Pass |
| Coordinates: | 47.4254°N -121.5524°W |
| Basin Countries: | United States |
| Elevation: | 4183feet |
| Islands: | none |
Mason Lake is a naturally occurring mountain lake located between Mount Defiance and Bandera Mountain near Snoqualmie Pass, King County, Washington.[1] Accessible only by hike via the 3.4miles Mason Lake Trail (also known as "Ira Spring Memorial Trail"),[2] splits to Mount Defiance trail while continuing past the Island Lakes towards Pratt Lake trail at Olallie Lake's north shore. Mason Lake is at an elevation of t.