In this paper, the effect of Web caching on network planning, in the sense of bandwidth computation for the access link interconnecting the ISP's subnet with the Internet, is studied by means of simulations. The latency of a browser retrieving files is studied for given traffic characteristics, number of users, bandwidth of access link, and cache hit rate. From our analysis, we find that using a well-designed Web cache with a 50% hit rate is more effective than doubling the bandwidth for an ISP's access link to the Internet, with respect to decreasing retrieval latency. In other words, we can reduce half of the bandwidth of the access link by using Web caching without compromising retrieval latency. The results are very encouraging and useful to the ISPs, enterprises and universities that are planning to interconnect their Intranets with the Internet.