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:
Westminster_Abbey

Context:
The abbey's two western towers were built between 1722 and 1745 by Nicholas Hawksmoor, constructed from Portland stone to an early example of a Gothic Revival design. Purbeck marble was used for the walls and the floors of Westminster Abbey, even though the various tombstones are made of different types of marble. Further rebuilding and restoration occurred in the 19th century under Sir George Gilbert Scott.

Question:
When were the western towers built?

between 1722 and 1745