1. A method for providing recommended lists of uniform resource locators (URLs) responsive to uniform resource locators (URLs), the method comprising: (a) receiving, by one or more servers of a linking system, a request to generate, for a first URL, a list of second URLs accessed by users that also accessed the first URL; (b) identifying, by the one or more servers of the linking system, multiple first shortened URL links generated by the one or more servers of the linking system, each of the multiple first shortened URL links linked to the first URL identified in the request; (c) for each first shortened URL of the multiple first shortened URL links: (i) identifying, by the one or more servers of the linking system, a plurality of users that clicked on the first shortened URL link of the multiple first shortened URL links; (ii) responsive to identifying the plurality of users that clicked on the first shortened URL link, identifying, by the one or more servers, a plurality of second shortened URL links clicked by each of the plurality of users, each of the plurality of second shortened URL links generated by the one or more servers of the linking system and linked to URLs corresponding to one or more destination servers; (iii) responsive to identifying a plurality of second shortened URL links clicked by each of the plurality of users, determining, by the one or more servers, for each second shortened URL link, a number of users who clicked on the second shortened URL link and also clicked on the first shortened URL link; and (iv) responsive to determining, for each of the second shortened URL links, the number of users who clicked on the second shortened URL link and also clicked on the first shortened URL link, enumerating, by the one or more servers, a list of URLs mapped, by the one or more servers of the linking system, to the second shortened URL links, each URL of the list of URLs mapped to one or more of the plurality of second shortened URL links; (d) responsive to enumerating, for each first shortened URL of the multiple shortened URL links, a list of URLs mapped to the second shortened URL links, generating, by the one or more servers, a second list of URLs by aggregating a plurality of the enumerated lists of URLs, the second list of URLs identifying second URLs accessed by users that also accessed the first URL identified in the request, each of the second URLs identified in the second list of URLs accessed by the users via a corresponding second shortened URL link shortened by the one or more servers of the linking system; and (e) providing, by the one or more servers, at least a subset of the generated second list of URLs as the recommended list of URLs in response to receiving the request to generate the list of second URLs accessed by users that also accessed the first URL.