3421 4th Street, Boulder, CO 80304 (MLS # IR1053821)

PRICE $6,800,000 dsIDX morgage calculator
BEDS 6
BATHS 5
HOME SIZE 5,022 sqft
LOT SIZE 26,136 sqft

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.

DAYS ON MARKET 104 LAST UPDATED 3/13/2026
TRACT Fourth Street 3403 Sub YEAR BUILT 1990
GARAGE SPACES 2.0 COUNTY Boulder
STATUS Active PROPERTY TYPE(S) Single Family

SCHOOLS
Elementary School Foothill
Jr. High School Centennial
High School Boulder


ADDITIONAL DETAILS
AIR Ceiling Fan(s), Evaporative Cooling
AIR CONDITIONING Yes
APPLIANCES Dishwasher, Disposal, Down Draft, Microwave, Oven, Refrigerator, Self Cleaning Oven
BASEMENT Daylight, Full, Yes
CONSTRUCTION Frame, Wood Siding
FIREPLACE Yes
GARAGE Yes
HEAT Forced Air, Hot Water, Radiant
INTERIOR Eat-in Kitchen, Open Floorplan, Vaulted Ceiling(s), Walk-In Closet(s)
LOT 0.6 acre(s)
LOT DESCRIPTION Rolling Slope, Sloped, Sprinklers In Front, Wooded
PARKING Oversized, Attached
SEWER Public Sewer
STORIES 3+
STYLE Contemporary
SUBDIVISION Fourth Street 3403 Sub
TAXES 26030
UTILITIES Cable Available, Electricity Available, Natural Gas Available
VIEW Yes
VIEW DESCRIPTION Mountain(s)
WATER Public
MORTGAGE CALCULATOR
   

TOTAL MONTHLY PAYMENT

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