Afoot means traveling on foot. Paul walked from Troas to Assos rather than taking the longer voyage around the cape.
Definition
Afoot means traveling on foot rather than by a vessel or other conveyance.
Biblical Usage
Paul went on foot from Troas to Assos.
Historical Background
Walking this route enabled Paul to avoid the tedious voyage around Cape Lectum.
Historical Bible Dictionaries
International Standard Bible Encyclopedia (ISBE)
<p>a-foot' (pezeuo, "to go on foot"): By walking from Troas to Assos Paul avoided the tedious voyage round Cape Lectum (Ac 20:13 the King James Version; compare Mr 6:33).</p>