Diamond Lake (Oregon)
lake in Douglas County, Oregon, United States
Diamond Lake is a natural body of water in the southern part of the U.S. state of Oregon. It lies near the junction of Oregon Route 138 and Oregon Route 230 in the Umpqua National Forest in Douglas County. It is located between Mount Bailey to the west and Mount Thielsen to the east; it is just north of Crater Lake National Park.
The outlet of the lake is at its north end. From there, water flows via Diamond Lake Creek into the North Umpqua River and ultimately to the Pacific Ocean.
Diamond Lake was named for John Diamond, for whom Diamond Peak is also named. He saw the lake in 1852 while on the summit of Diamond Peak. Diamond was a pioneer settler of Coburg, Oregon, and part of a party opening a road between the Middle Fork Willamette River and Idaho as an immigration route.
An adjacent post office named Diamond Lake, Oregon, was established in 1925 and ran until 1956, when it was changed to a summer-only office.
Diamond Lake is also the host for the Tour de Diamond, a cycling event that happens every summer.
The public source identifies “Diamond Lake (Oregon)” as lake in Douglas County, Oregon, United States. This brief keeps that definition visible, then builds a research path around Diamond, Lake and Oregon.
Why this record matters
A short description can identify a subject without explaining its stakes. For “Diamond Lake (Oregon)”, the useful work is to connect “lake in Douglas County, Oregon, United States” to the records capable of establishing context and consequence.
Place names and jurisdictional language are key evidence: both can reveal earlier catalogue descriptions and overlooked record series. The source revision retrieved here is dated Jul 25, 2026. The linked authority identifier is Q821118. VIAF identifies the subject as 315149964. The Library of Congress control number is sh95001524. Authority coordinates are 43.160, -122.152. 3 of 4 selected statements include explicit references; 0 carry qualifiers and 0 use preferred rank. The first chronological checks are 1852, 1925 and 1956.
Modern boundaries and familiar names can conceal earlier jurisdictions or structures that do not align with the present site. The lead is largely declarative, so disagreement and counter-evidence require a deliberate search beyond the opening account. Authority statements aid reconciliation but still require their own references, qualifiers and ranks to be checked.
How to read it
Treat names, boundaries and functions as historically changeable. Maps, plans, inventories and administrative records can clarify what the place meant at different dates.
- Historic place names
- Jurisdictional context
- Routes into maps and plans
Contemporary maps, plans, listed-building records, estate papers and the responsible local or national archive.
Three-step research path
- Establish the record: confirm the title “Diamond Lake (Oregon)”, its source revision and the description used here.
- Expand the search: follow Diamond Lake (Oregon) primary sources, Diamond Lake (Oregon) archive and Diamond research across catalogues and specialist indexes.
- Test the account: compare the strongest cited source with the responsible institution’s current record and note any disagreement.
Questions for further research
- Which source most directly establishes the central claim about “Diamond Lake (Oregon)”?
- Which earlier names or jurisdictions may reveal additional records?
- What physical evidence or contemporary plan supports the description?
Search terms from this dossier
This entry incorporates text from “Diamond Lake (Oregon)” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.