Athlone was a siding of the Southern Pacific Railroad located in Merced County on the alignment of what was US Route 99 between the cities of Chowchilla and Merced. The Athlone corridor of US Route 99 was one of the first in San Joaquin Valley to fully upgraded to four lane expressway standards. The Athlone expressway corridor was inherited by California State Route 99 when US Route 99 was truncated to Ashland, Oregon during June 1965. The four-lane expressway through Athlone was the last segment of what had been US Route 99 in the Wheeler Ridge-Sacramento corridor to be bypassed by a freeway. The Athlone expressway corridor was bypassed by the modern California State Route 99 freeway in 2016. Despite being put on a road diet and narrowed what was the Athlone expressway corridor still displays evidence of being part of US Route 99.
Above the blog cover photo displays the Athlone expressway corridor of US Route 99 south of Merced as depicted in the July 1939 California Highways & Public Works. Below US Route 99 can be seen passing through Athlone on the 1935 Division of Highways Map of Merced County.
Part 1; the history of US Route 99 and California State Route 99 through Athlone
Athlone was founded 1874 along the main freight line of the Southern Pacific Railroad in San Joaquin Valley as a siding facility and town site. Athlone was named in honor of an Irish community of the same name. Athlone was largely not successful growing beyond it's siding origins as the community had sporadic Post Office service from 1881 to 1937. Athlone can be seen along the Southern Pacific Railroad on the 1882 Bancroft's Map of California and Nevada.
US 99/LRN 4 can be seen passing through Athlone on the 1935 Division of Highways Map of Merced County.
The Ocotber 1941 California Highways & Public Works discusses the widening of US 99/LRN 4 in the Mecred Area. The improvements to US 99/LRN 4 in the Merced saw several new bridges installed, namely at Bear Creek in 1940 which saw the removal of the Redwood Gateway Arch. US 99/LRN 4 between Chowchilla-Merced is stated to have been completed to four-lane expressway standards by June 1939. Active construction to upgrade the remainder of US 99/LRN 4 between Merced-Chowchilla to expressway standards is stated to be underway and would include a new bridge over the Chowchilla River.
The Chowchilla Freeway upgrade of US 99 is discussed in the March/April 1957 California Highways & Public Works. The Chowchilla Freeway is described as being aligned east of Chowchilla Boulevard on a new bypass route for US 99/LRN 4. The 1930 Southern Pacific Railroad subway is discussed as being converted from two-way traffic to use exclusively for northbound US 99 traffic. The US 99/CA 152 junction upgrade is described as being converted from being at-grade to a series of ramps. Work on the Chowchilla Freeway is described as having broken ground on March 23rd, 1956 with an anticipated completion coming in July 1957. The Chowchilla Freeway corridor would tie into the existing expressway towards Merced via Athlone near Vista Avenue in Merced County.
The July/August 1964 California Highways & Public Works announced the completion of the Merced Freeway realignment of US 99 in Merced. The Merced Freeway is cited to have begun during July of 1960 and opened between Gerard Avenue north to the Atwater Bypass in June 1964. Upon the completion of the Merced Freeway CA 140 moved to a multiplex of US 99 from 16th Street to V Street. CA 59 subsequently moved to a multiplex of US 99 from R Street (current Martin Luther King Jr. Way) to V Street. The project map depicts the Merced Freeway tying into the existing expressway towards Chowchilla via Athlone expressway at Gerald Avenue.
The May 2015 Google Street View image reveals southbound CA 99 using Kahlon Road whereas the former northbound expressway lanes are shown to be razed.