The methods illustrated in this paper address one particular kind of 'trace', the hyperlink, and the use of this trace to help constitute a field of study. We suggest that an ethnographic treatment of hyperlinks can be a useful way to understand the Internet as a space for knowledge production. Via a consideration of hyperlinks as both functional and symbolic, this approach suggests how traditional elements of ethnography might be adapted in order to constitute an online field site for the study of infrastructure. The methods discussed in this paper were elaborated in the course of two projects using virtual ethnography (Hine, 2000). Both focused on new infrastructure for knowledge production (databases) which had a web interface. Common to both projects was the notion that these databases might be involved in shifts in the locus of knowledge production. In other words, the lab as a 'site' may be an increasingly networked, digitised setting. If part of the original motivation for going into the lab for studying science was to visit the place where knowledge was said to originate, the same holds for taking online settings seriously, as a site where knowledge is also arising. Networked knowledge production, however, challenges the traditional approaches to constructing the field for lab studies. The traces chosen as constitutive of the field in our research, hyperlinks, led to a complex, multilayered understanding of interpretive context around the various databases investigated. Paying attention to aspects of connectivity (specificity, origin, timescape, and symbolic and infrastructural dimensions of hyperlinks) may help to build a richer notion of various instantiations of the Internet. The focus in this article is on the notion of time, and on the ways knowledge about various aspects of time may be investigated ethnographically, using hyperlinks as traces.