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Boulder, CO 80304 3421 4th St

OPEN HOUSE Sun, Apr 12 2026 12:00 PM - 04:00 PM
OPEN HOUSE Sat, Apr 18 2026 12:00 PM - 04:00 PM
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Presented By: ;
  • MLS# 1053821
  • 03/13/2026
  • Request Tour
  • Request Info
  • Beds • 6
  • Full/Half Baths • 4 / 1
  • Garage • 2

Home Details

Newlands Sanctuary on Mt. Sanitas Open Space Step onto the 600-square-foot deck and look up. Mt. Sanitas rises 1,300 feet from your backyard gate, private access to the Goat Trail. No driving. No parking. Just you, your coffee, and maybe a 4-legged friend who will make sure you don't skip it. This premier property is one of eight homes backing directly to open space. In 21 years, only one has changed hands. Hidden behind a 70-yard tree-lined driveway on a 0.6-acre lot (2.5x standard), this is widely regarded as one of Boulder's best addresses, served by top rated schools.The 5,200-square-foot residence features 20-foot ceilings with west-facing glass framing Mt. Sanitas, white oak floors, two fireplaces, and a library overlooking the property's seven heritage apple trees. Six bedrooms plus office (convertible seventh) include three distinct suites: the primary en-suite with a stunning view; a garden-level walkout in-law addition (2005, 12' ceilings) with separate entrance, private patio, and dedicated office-ideal for multigenerational living or guests-plus a basement suite with whirlpool bath. Outside you will discover a deep wrap-around porch beneath a 60-foot silver maple, flower and vegetable gardens, and the historic Silver Lake Ditch with 12,000 gallons daily water rights. Sundance Film Festival arrives January 2027, venues minutes away providing a chance at an incredible rental income opportunity and under the Augusta Rule, 14 days of rental income may be tax-free. Roof replaced 2019. New carpet. Heated two-car garage. No HOA. No covenants. For those who know Newlands: this is the privacy, the lot, the view, and the trail access that almost never comes to market. For those discovering Boulder for the first time: welcome to the neighborhood the locals covet most.
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Interior Features for 3421 4th St

Bedrooms

Total Bedrooms6

Bathrooms

3/4 Baths2
Half Baths1
Total Baths5

Other Interior Features

LivingAreaSourceOther
Above Grade Finished Area3927
BasementFull, Partially Finished, Daylight
Below Grade Finished Area1271
Fireplace FeaturesTwo or More, Gas, Gas Log, Living Room, Family Room
Interior AmenitiesEat-in Kitchen, Separate Dining Room, Cathedral Ceiling(s), Open Floorplan, Walk-In Closet(s)

General for 3421 4th St

AppliancesGas Range, Down Draft, Self Cleaning Oven, Dishwasher, Refrigerator, Microwave, Disposal, Fire Alarm
Architectural StyleLegal Conforming, Contemporary
AttributionContact9705317448
CityBoulder
Construction MaterialsFrame, Wood Siding
CoolingEvaporative Cooling, Ceiling Fan(s)
CountyBoulder
DirectionsFrom Broadway, turn left on Juniper Ave. Turn right on 4th St. Property on left side.
DisclosuresSeller's Property Disclosure
ElectricXcel
Elementary SchoolFoothill
ExclusionsFurnishings and Personal Property
Expected Active Date 2026-03-13
Full Baths2
Garage Spaces2
HOANo
HeatingForced Air, Hot Water, Zoned, Radiant, 2 or more Heat Sources
High SchoolBoulder
High School DistrictBoulder Valley Dist RE2
LevelsFour
Living Area5022
MLS AreaBoulder
Middle/Junior High SchoolCentennial
New ConstructionNo
Parcel NumberR0108936
Patio/Porch FeaturesPatio, Deck
Possible UseSingle Family
Property Attached Y/NNo
Property SubtypeSingle Family Residence
Property TypeResidential
RoofComposition
SewerPublic Sewer
Spa FeaturesBath
Standard StatusActive
StatusActive
Subdivision NameFourth Street 3403 Sub
Tax Annual Amount26030
Tax Year2025
UtilitiesNatural Gas Available, Electricity Available, Cable Available, High Speed Avail
ViewHills
Year Built1990
ZoningSFR

Exterior for 3421 4th St

Exterior AmenitiesSprinkler System, Oversized Garage
FencingPartial, Fenced, Wood, Chain Link
Irrigation Water Rights Y/NNo
Lot FeaturesWooded, Evergreen Trees, Deciduous Trees, Sloping Lot, Abuts Ditch, Abuts Public Open Space, House Faces East, Paved, Water Rights Included
Lot Size Acres0.6
Lot Size Area26072
Parking FeaturesGarage Door Opener, Attached
Road Frontage TypeCity Street
Road Surface TypeAsphalt
Water SourceCity
Waterfront Y/NNo

Additional Details

Price History

Schools

High School Boulder High School
Elementary School Foothill Elementary School
Middle School Centennial Middle School

Nathan Washam

Broker/Owner
Price $6,800,000
MLS#1053821
List Date 03/13/2026
Property Type Single Family
Phone 970.988.8295
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