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Home » Real Estate » CO » Boulder » 80304 » 3421 4th St, Boulder, CO, 80304
$6,800,000

3421 4th St, Boulder, CO, 80304

6 Beds
5 Baths
5,198 Square Feet

Open House

March 14 12:00 pm - 4:00 pm

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.
Offered By
Kathleen Haas, Colorado Realty 4 Less, LLC

Property Details

Property Type Residential
Status Active
Bedrooms 6
Bathrooms (Full) 2
Property Sub Type Single Family Residence
Square Feet 5,198
MLS # 1053821
Bathrooms (¾) 2
Bathrooms (Half) 1

Market Trends

New Properties On Market
66
57% Increase In New Listings
Average Asking Price
$2,625,148
$198,545 Decrease In Avg Asking Price
Average Asking Price / Sq. Ft.
$827
$70 Decrease In List Price/Sq. Ft.
Average Days On Market
13
26 Day Decrease In Days On Market
Data as of Mar 13, 2026. Remaining statistics above are calculated on activity within the period from Jan 01, 2026 to Feb 28, 2026.

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