Feature 'f' is a hornwork[1]
Hornwork
The Weber Church of Zittau inside a hornwork[2]
Drawing, showing a hornwork, of the fortress Nya Älvsborg in Gothenburg, Sweden from 1811.
Drawing, showing a hornwork, of the fortress Nya Älvsborg in Gothenburg, Sweden from 1811.

A hornwork is an element of the Italian bastion system of fortification. Its face is flanked with a pair of demi-bastions.

It is distinguished from a crownwork, because crownworks contain full bastions at their centers. They are both outworks.

References

  1. ^ From Cyclopaedia
  2. ^ Europaeum Theatrum, Volume 5, plate 12. Published in 1651 in Frankfurt am Main.