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3421 4th St, Boulder, CO 80304
3421 4th St, Boulder, CO 80304
3421 4th St, Boulder, CO 80304
3421 4th St, Boulder, CO 80304
3421 4th St, Boulder, CO 80304
3421 4th St, Boulder, CO 80304
3421 4th St, Boulder, CO 80304

3421 4th St Boulder, CO 80304

$6,800,000

ACTIVE
Beds
6
Baths
5
Sqft
5,022
Acres
0.6
Year
1990
Days on Site
21
Property Type
Residential
Sub Type
Single Family
Per Square Foot
$1,354
Date Listed
Mar 13, 2026

Description of 3421 4th St, Boulder, CO 80304

Listing details for 3421 4th St, Boulder, CO 80304 : 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.
Listing Updated : 03-29-2026 at 8:00 PM MDT
Listing Provided By : Kathleen Haas, 9705317448, Colorado Realty 4 Less, LLC
Source :

recolorado as distributed by MLS GRID, MLS#: RECIR1053821

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Based on information submitted to the MLS GRID as of 2026-04-03 at 5:00 a.m. MDT. All data is obtained from various sources and may not have been verified by broker or MLS GRID. Supplied Open House Information is subject to change without notice. All information should be independently reviewed and verified for accuracy. Properties may or may not be listed by the office/agent presenting the information.

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