open to public access. Plots could be rented or bought, with or without user-ready or customised tombs. The great cemetery of Isola Sacra and the tombs that line both sides of the Via Appia Antica offer notable examples of roadside cemeteries In the city of Rome, tombs also lined both embankments of the Tiber, a major waterway whose towpaths and wharves were in near-constant use. Tombs were still being built there in the Imperial era, despite the hindrances they must have posed to businesses at docks and wharves, and the planning, building and maintenance of riverine roadways, bridges and aqueducts. Rome was virtually encircled by its dead. Cemeteries, tombs and their dead were protected by religious and civil laws and interdicts; A place used for burial was a locus religiosus; it belonged to the Manes gods because a body was buried there, or found there. Its disturbance was thought to cause pain and discomfort to the deceased, whether senator or slave. The discovery of any previously unknown interment on profane (public or private) land created an immediate encumbrance to its further use; it had revealed itself as a locus religiosus, and remained so unless the pontifs agreed to revoke its status and remove the body or bones. Death by lightning strike was thought a clear statement by Jupiter that the place and the victim belonged to him; the place was marked out accordingly, and the victim buried, though not with "ordinary rites". Cicero records a major pontifical decision that any grave in publicly owned land was unlawful, and therefore could not be treated as a locus religiosus. The decision paved the way for a mass exhumation of cemetery land just outside Rome's Colline Gate, and its eventual re-use as public land. At more or less the same time, cremation hearths (ustrina) and rubbish dumping were banned from the Esquiline and for 2 miles beyond the city wall. Cicero thought that all this had to do with minimising the risk of fires; that was a factor, but the Esquiline's odour was a more immediate and notorious public nuisance. Augustus' ally Maecenas covered the site with 25 feet depth of soil, built himself a luxury urban villa there and opened its extensive gardens to the public, all at his own expense; this earned him much credit as a public benefactor. Various funerary structures built on Rome's outskirts by wealthy patrons around this