Complex sentence: The Venetians subsequently dismantled it, fearing it could be captured by their enemies or even by the locals and used against them and even in later times did not repair or maintain it, in contrast to their efforts at strengthening Angelokastro and the Old Fortress of Corfu.
Split into simpler sentences: The Venetians subsequently dismantled it, fearing it could be captured by their enemies, or by the locals, and used against them. Even in later times they did not repair or maintain it, in contrast to their efforts at strengthening Angelokastro and the Old Fortress of Corfu.