Davao del Sur's 1st congressional district
Davao del Sur's 1st congressional district is an obsolete congressional district in Davao del Sur for the House of Representatives of the Philippines from 1987 to 2016. The district encompassed seven northern local government units of the previously undivided province bordering Davao City and includes Digos, the provincial capital. It was created ahead of the 1987 Philippine House of Representatives elections following the ratification of the 1987 constitution which established two districts for the province and another three districts for Davao City. Prior to the 1987 apportionment, Davao del Sur residents elected  their representatives to the national legislatures on a provincewide basis through the Davao del Sur's at-large congressional district. The district was last contested at the 2013 Philippine House of Representatives elections. Davao del Sur returned to electing its representatives at-large in 2016 after losing most of its southern territory to the province of Davao Occidental created by Republic Act No. 10360 on January 4, 2013.