From Ac 27:29-30,40, it would appear that the Roman vessels carried several anchors, which were attached to the stern as well as to the prow. The Roman anchor, like the modern one, had two teeth or flukes. In Heb 6:19 the word is used metaphorically for that which supports or keeps one steadfast in the time of trial or of doubt. It is an emblem of hope.
If you fear, Put all your trust in God: that anchor holds.
The anchors used by the ancients were in shape somewhat like the modern ones, as may be seen on some of the coins. When Paul was on his way to Rome, four anchors were needed to hold the ship. Ac 27:29-30,40. The anchor is used metaphorically for the hope set before the Christian, it enters into that within the veil, and is sure and steadfast. It was a great thing for the Hebrew believers to have their eyes turned to heaven; the anchor of their hope was there; no matter what storms they might meet with, the realisation of their hope was certain if set on Christ. Heb 6:19.