Courthouse Site 1865 1909. Dayton was the first seat of Lyon County and had one of the first courthouses built in Nevada.  Finished in 1864, local residents celebrated the new two-story brick building and its Italianate styling as an important architectural benchmark for a new state.On the afternoon of May 15, 1909, the two-story brick building burned and the county seat was moved to Yerington two years later.  Utilizing the ruins, the Nevada legislature funded the construction of a high school that opened in 1918.  The school closed in 1959 and the building became an elementary school, then a junior high school and is now the Dayton Valley Community Center.