Discover 120 Keystone St, a premier 52-acre legacy estate for sale in the exclusive Elkhorn area of Sun Valley, Idaho. Positioned just minutes from downtown Ketchum and the Sun Valley Resort, this rare dual-parcel landholding–comprising 18.6 and 33.5 acres–offers an unparalleled opportunity for a private equestrian compound or a boutique luxury residential development. Bordering U.S. Forest Service land, the property provides direct, private canyon access for horseback riding, hiking, and outdoor recreation right from your back door.
Appraised at $10.5M, this Sun Valley real estate asset combines pristine natural amenities with exceptional utility. The land is anchored by senior 1883 water rights for irrigation and stock, a high-yield well, and a serene pond with on-site geothermal potential. Ready for immediate development, the property features BC/R-10 zoning with patented mining claims, along with installed infrastructure including well, septic, and buried power.
Significant value-add and investment upside include a prospective 18-acre USFS land swap to expand contiguous acreage, as well as a recent site analysis indicating potential for a third building site to increase overall density. As one of the last large private landholdings in a supply-constrained Blaine County market, the seller is offering flexible acquisition terms, including owner financing (owner carry paper) for up to five years with 50% down. Search “120 Keystone St Sun Valley” on YouTube to view complete video tours.
Appraised at $10.5M, this Sun Valley real estate asset combines pristine natural amenities with exceptional utility. The land is anchored by senior 1883 water rights for irrigation and stock, a high-yield well, and a serene pond with on-site geothermal potential. Ready for immediate development, the property features BC/R-10 zoning with patented mining claims, along with installed infrastructure including well, septic, and buried power.
Significant value-add and investment upside include a prospective 18-acre USFS land swap to expand contiguous acreage, as well as a recent site analysis indicating potential for a third building site to increase overall density. As one of the last large private landholdings in a supply-constrained Blaine County market, the seller is offering flexible acquisition terms, including owner financing (owner carry paper) for up to five years with 50% down. Search “120 Keystone St Sun Valley” on YouTube to view complete video tours.
Property Details
Price:
$4,900,000
MLS #:
26-334170
Status:
Active
Beds:
0
Baths:
0
Type:
Land
Subtype:
Single Family Residence
Neighborhood:
elkhorninsunvalley
Listed Date:
Mar 12, 2026
Lot Size:
2,265,120 sqft / 52.00 acres (approx)
See this Listing
Schools
Interior
Exterior
Fencing
Fenced
Other Structures
Barn(s), Corral(s), Outbuilding
View
See Remarks
Waterfront Features
Pond, See Realtor Remarks, Wetlands
Financial
Tax Year
2025
Taxes
$1,207
Map
Community
- Address120 Keystone St Sun Valley ID
- SubdivisionOther
- CitySun Valley
- CountyBlaine
- Zip Code83353
Subdivisions in Sun Valley
Market Summary
Current real estate data for Land in Sun Valley as of Sep 14, 2026
7
Land Listed
91
Avg DOM
$2,591,429
Avg List Price
Property Summary
- Located in the Other subdivision, 120 Keystone St Sun Valley ID is a Land for sale in Sun Valley, ID, 83353. It is listed for $4,900,000 and features 52 acres. To schedule a showing of MLS#26-334170 at 120 Keystone St in Sun Valley, ID, contact your Ralston Group Properties, LLC agent at 2087035666.
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