Las Flores is a small archaeological site, but its location makes it memorable: a Huastec mound inside the modern city rather than out in a remote ruin zone. The main structure dates from the Postclassic period and is tied to the wider Huastec culture of the Gulf coast.
There is not much interpretive infrastructure, so bring realistic expectations. The point is the survival of the site in urban Tampico, not a grand pyramid complex.