From the Beeler Organization for the City Council.

Appendix I: Seattle Municipal Street Railway: Dates of Abandonment of Individual Routes

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Route 4: Lake Burien
Abandoned:
Cut to White Center – 15 July 1931
Through service cut by slide – 17 December 1933
Cut at Burien Way and W. Marginal until 29 January 1934
Shuttle #357 operated White Center to 9th & Holden from 18 Dec 1933 to 28 Sep 1934
Abandoned on latter date. Shuttle operated on West Marginal Way from 19 January 1934 to 19 December 1937.

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One–man conversion dates (Compiled by Lawton Gowey)
4 Lake Burien, 18 June 1923