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Los Alamos County

Los Alamos County is named after the Los Alamos School for Boys, established in 1925 by Ashley Pond.


Surrounding County Courthouses: 

N – Sandoval County

E – Rio Arriba County and Santa Fe County

S – Santa Fe County and Sandoval County

W – Sandoval County

Created:  March 16 1949                        Map of New Mexico highlighting Los Alamos County

County Seat:

Los Alamos  1949 – present


County Courthouse – Los Alamos  


Location:   2500 Trinity Drive / Openheimer Drive

Built:  2008 – 2010

Style:   Modern

Architect:  WH Pacific of Albuquerque

Contractor:  H B Construction of Albuquerque


Description: The building faces north and is a two story red colored brick, glass and concrete structure. The building is located on landscaped grounds in the center of Los Alamos.  The north front has a central red colored brick center with entrances on either side and glass panel walls above. The roof forms a pyramid at the rear. In the interior, the County District Court courtroom and the County Magistrate courtroom are located on the second story. The building is named as the Justice Center and houses the County District Court of the 1st Judicial District and the County Magistrate Court.


Former County Courthouse – Los Alamos  



Location:   2300 Trinity Drive / Openheimer Drive

Built:  1966 – 1967

Style:   Modern

Architect:  Fialow, Moore, Bryan & Fairbon

Contractor:  Franklin Construction Company


Description: The building faced east and was a two story glass and concrete structure. On the east side were landscaped grounds with a small lake. The east front and the south and north sides, had large concrete pillars with recessed windows. The roof projected from the building. The building housed the County Government, City Offices and the Municipal Court as Los Alamos is a city and county combined under one jurisdiction. The building was demolished in 2008.


See:  The 1st Judicial District includes Rio Arriba County and Santa Fe County.


History:  The county was created in 1949 and Los Alamos was selected as the county seat. The first courthouse was the converted two story Sundt Building which was used from 1956 to 1967. The second courthouse was constructed in 1966 to 1967 and demolished when the third and present courthouse was constructed in 2008 to 2010 at a cost of $50,000,000.


County Administration Building – Los Alamos



Location:   1000 Central Avenue / 10th Street

Built:  2008 – 2010

Style:   Modern

Architect:  Studio Southwest Architects Inc. of Albuquerque

Contractor:  Jaynes Corporation of Albuquerque.



Description: The building faces west and is a three story glass and concrete structure. The west front and east side have high rectangular concrete arches with recessed entrances. Along the south side are concrete pillars with recessed walls. The building has large glass panel windows and a flat roof line. The building is named as the Municipal Building and houses the County Probate Court.



County Courthouse –  Los Alamos

















County Magistrate Court courtroom





Former County Courthouse ( demolished ) – Los Alamos









County Administration Building – Los Alamos









Photos taken 2007 and 2016