The expedition matters to the spine chiefly as the origin of the Ionian tyrants' guardianship of the Danube bridge, which Herodotus makes the hinge of the Ionian Revolt narrative at 4.137–139 and 5.11.就时间轴而言，此役的要紧处在于伊奥尼亚僭主受命守多瑙河桥一节；希罗多德在 4.137–139 与 5.11 以此为伊奥尼亚起义叙事的枢纽。
The accounts记述 · the ancient witnesses
Greek historians · 希腊史家
Herodotus — Histories （希罗多德·历史）primary source · 源典
§ 4
Hdt. 4.83–144 — the Bosporus bridge, the march beyond the Danube, the Scythians' refusal of battle, the debate at the Danube bridge and the Persian withdrawal; Bk 4 as a whole is the Scythian logos希罗多德 4.83–144——博斯普鲁斯架桥、越多瑙河进军、斯基泰人避战、多瑙河桥头的争议与波斯撤军；第四卷整卷即斯基泰志
Provenance: “primary source” = curated canonical witness (editorial); “dated witness” = derived from the ToposText date index by year-span, with the matched loci count. Sparse counts may include incidental mentions.出处：「源典」为校订之正典见证（编辑判断）；「系年见证」由 ToposText 系年索引按年代跨度推得，附匹配条目数；稀少者或含偶涉。
On the timeline时间轴上
→ See this and all 18 historians on the chronology spine于编年脊柱上一览本事件与全部 18 位史家