Mountain Homes Realty
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3421 4th street

Boulder, CO 80304

$6,800,000

6 BEDS 5 BATHS
5,022 SQFT
Residential - Single Family
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Bedrooms 6
Total Baths 5
Full Baths 2
Square Feet 5022
Status Active
MLS # IR1053821
County Boulder
More Info
Category Residential - Single Family
Status Active
Square Feet 5022
MLS # IR1053821
County Boulder
Listed By: Listing Agent Kathleen Haas
Colorado Realty 4 Less, LLC - (970) 531-7448
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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Exterior Features

  • Style Contemporary
  • Construction Single Family Residence
  • Siding Frame, Wood Siding
  • Roof Composition
  • Garage No
  • Garage Description Oversized
  • Water Public
  • Sewer Public Sewer
  • Lot Description Ditch, Open Space, Rolling Slope, Sprinklers In Front

Interior Features

  • Appliances Dishwasher, Disposal, Down Draft, Microwave, Oven, Refrigerator, Self Cleaning Oven
  • Heating Forced Air, Hot Water, Radiant
  • Cooling Ceiling Fan(s), Evaporative Cooling
  • Fireplaces Description Family Room, Gas, Gas Log, Living Room
  • Living Area 5,022 SQFT
  • Year Built 1990

Neighborhood & Schools

  • Subdivision Fourth Street 3403 Sub
  • Elementary School Foothill
  • Middle School Centennial
  • High School Boulder

Financial Information

  • Parcel ID R0108936
  • Zoning SFR

Additional Services

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Listing Information

Listing Provided Courtesy of Colorado Realty 4 Less, LLC - (970) 531-7448
Listings courtesy of the RE Colorado MLS as distributed by MLS GRID.

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Listing data is current as of 07/06/2026.

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