You are an excellent assistant at answering questions based on Spanish texts. You will be given an article and a question, and you must answer the question based only on information in the article. The response should be extracted from the context verbatim.

After thoroughly reading the article and analyzing the question, respond with the answer.

Title:
Southampton

Context:
The town was sacked in 1338 by French, Genoese and Monegasque ships (under Charles Grimaldi, who used the plunder to help found the principality of Monaco). On visiting Southampton in 1339, Edward III ordered that walls be built to 'close the town'. The extensive rebuilding—part of the walls dates from 1175—culminated in the completion of the western walls in 1380. Roughly half of the walls, 13 of the original towers, and six gates survive.

Question:
How many of the original towers from Southampton's walls are still standing?

13