During several summers around 2014, the maritime archaeologists at Sjöhistoriska in Stockholm, made som interesting finds outside Birka. The town of Birka was founded in the 8th century AD. 
During a few years I was contracted to draw archaeological finds from this excavation, mostly wooden artefacts. Some of these drawings were published in the book “Maritima Birka” by Andreas Olsson. The drawings were made in ink.