Cross section of the West-East Section at core O position.

<p>Cross section of the West-East Section at core O position.</p

Stratigraphical documentation of the KG 256 cross section within the North-Eastern Section.

<p>The cross section shows the in situ layers of the Rezat fen in the East and the trench structure in the West. For the first time there is in situ evidence for a Carolingian trench in the North-Eastern Section. The trench bottom is shown by horizontal bars.</p

Synthetic longitudinal profile of the Fossa Carolina from Graben to Rezat River.

<p>a) The red line shows the Pre-Carolingian surface and watershed, the red dot indicates the summit the natural watershed. b) The short horizontal bars feature the Carolingian levels of excavation deduced from the drilling stratigraphies, and the blue dot indicates the artificial summit of the Carolingian trench bottom. c) The solid black line represents the level of the recent trench surface following the course of the canal.</p

Digital elevation model of the Central Section including detailed drilling positions.

<p>Raw data source: LIDAR data are cordially provided by Bavarian Land Surveying Office for illustrative purposes.</p

Types of sediment texture in the Central Section and the West-East Section.

<p>a) fluvial type and b) ponding type.</p

Stratigraphical documentation of the QP cross section within the Northern Section of the canal.

<p>The drawing shows a 42 m long cross section with the different facies types and the Carolingian level of excavation.</p

The local topographical setting of the Fossa Carolina.

<p>The canal is located across a valley watershed between the Altmühl River (Danube catchment) and the Swabian Rezat River (Rhine-Main catchment) within the Treuchtlingen valley junction at the piedmont of the Franconian Jura escarpment. Data source: Open access SRTM data (3 arc-second, 90 m raster, <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0108194#pone.0108194-Greenbelt1" target="_blank">[72]</a>) and OpenStreetMap <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0108194#pone.0108194-OpenStreetMap1" target="_blank">[73]</a>.</p

West-East Section of the Fossa Carolina.

<p>The figure shows a digital elevation model with detailed drilling positions, electrical transects, and the flux gate magnetic survey. White dots mark the drilling positions. The black lines show the geo electrical transects 1 and 2. Raw data source: LIDAR data are cordially provided by Bavarian Land Surveying Office for illustrative purposes.</p

Geoarchaeological findings of the different canal sections: summarizing overview.

<p>A plus sign (+) indicates clear <i>in situ</i> stratigraphical and chronological evidence, a circle (o) feature additional research needs, and a minus sign (-) indicates no <i>in situ</i> evidence.</p><p>Geoarchaeological findings of the different canal sections: summarizing overview.</p

Stratigraphical documentation of the KG 407 cross section within the Northern Section of the canal.

<p>The drawing shows a 90 m long cross section with the different facies types and the Carolingian level of excavation.</p