Pliny the Elder (23-79 AD) was born in Como. He held various posts in the Imperial administration. He became commander of the fleet at Misenum, and died of suffocation during the eruption of Mount Vesuvius in 79 AD. His only work to survive is On Natural History. Bill Thayer has made the Latin text of the "Naturalis Historia" available on the web. Below are passages related to Ostia and Portus.

Naturalis Historia
II.lxvi.121 - consuetudo omnibus his nominibus argesten intellegit. caecian aliqui vocant Hellespontian, et eosdem alii aliter. item in Narbonensi provincia clarissimus ventorum est circius nec ullo omnium violentia inferior, Ostiam plerumque secto Ligustico mari perferens. idem non modo in reliquis partibus caeli ignotus est, sed ne Viennam quidem eiusdem provinciae urbem attingens: paucis ante milibus iugi modici occursu tantus ille ventorum coercitus! II.lxvi.121 - '[speaking of the wind called 'Olympias']: by all these names the argestes is customarily meant. As for the caecias some call it the Hellespontine, and other people call these winds by other names. Similarly, in Narbonensis province the most famous of the winds is the circius, second to none in its force, usually propelling [ships] straight to Ostia by cutting across the Ligurian Sea: yet not only is this wind unknown in the other quarters of the sky, but it doesn't even reach Vienna [modern Vienne] in the very same province: a few miles before it this mighty wind is checked by the interposition of a range of rather average height!'

Translation: Bill Thayer.
III.v.56 - Latium antiquum a Tiberi Cerceios servatum est m. p. L longitudine: tam tenues primordio imperi fuere radices. colonis saepe mutatis tenuere alii aliis temporibus, Aborigenes, Pelasgi, Arcades, Siculi, Aurunci, Rutuli et ultra Cerceios Volsci, Osci, Ausones, unde nomen Lati processit ad Lirim amnem. in principio est Ostia colonia ab Romano rege deducta, oppidum Laurentum, lucus Iovis Indigetis, amnis Numicius, Ardea a DanaŽ Persei matre condita. III.v.56 - 'Old Latium from the Tiber to Cerceii is a distance of 50 miles: so slight were the roots of our early extension. Settlers came and went, among which at various times the original inhabitants, the Pelasgi, the Arcades, the Siculi, the Aurunci and the Rutuli -- and beyond Cerceii the Volsci, the Osci, and the Ausones, whence the name of Latium was extended up to the Liris river. First comes Ostia, a colony established by a king of Rome, then the oppidum of Laurentum, the grove of Jupiter Indiges, the Numicius river, and Ardea, founded by Danae, the mother of Perseus.'

Translation: Bill Thayer.
VII.iii.33 - Tergeminos nasci certum est Horatiorum Curiatiorumque exemplo. super inter ostenta ducitur praeterquam in Aegypto, ubi fetifer potu Nilus amnis. proxime supremis Divi Augusti Fausta quaedam e plebe Ostiae duos mares, totidem feminas enixa famem, quae consecuta est, portendit haud dubie. VII.iii.33 - 'That triplets are born is certain: we have the example of the Horatii and the Curiatii. More than that is viewed as a portent, except in Egypt where the water of the river Nile has the qualities of a fertility drug. When in recent times, at the funeral of Augustus of blessed memory, a plebeian woman named Fausta at Ostia was delivered of two boys and two girls, it was quite undoubtedly a portent of the famine that followed.'

Translation: Bill Thayer.
IX,v,14-15 - orca et in portu Ostiensi visa est oppugnata a Claudio principe. venerat tum exaedificante eo portum, invitata naufragiis tergorum advectorum e Gallia, satiansque se per conplures dies alveum in vado sulcaverat, adtumulata fluctibus in tantum, ut circumagi nullo modo posset et, dum saginam persequitur in litus fluctibus propulsam, emineret dorso multum super aquas carinae vice inversae. praetendi iussit Caesar plagas multiplices inter ora portus profectusque ipse cum praetorianis cohortibus populo Romano spectaculum praebuit, lanceas congerente milite e navigiis adsultantibus, quorum unum mergi vidimus reflatu belvae oppletum unda. IX,v,14-15 - 'A killer whale was actually seen in the harbor of Ostia, locked in combat with the emperor Claudius. She had come when he was completing the construction of the harbor, drawn there by the wreck of a ship bringing leather hides from Gaul, and feeding there over a number of days, had made a furrow in the shallows: the waves had raised up such a mound of sand that she couldn't turn around at all, and while she was pursuing her banquet as the waves moved it shorewards, her back stuck up out of the water like the overturned keel of a boat. The emperor ordered that a large array of nets be stretched across the mouths of the harbor, and setting out in person with the praetorian cohorts gave a show to the Roman people, soldiers showering lances from attacking ships, one of which I saw swamped by the beast's waterspout and sunk.'

[I realize Loeb has something very different for adsultantibus, and I believe them to be quite wrong. Their version for lanceas congerente milite e navigiis adsultantibus reads: 'the soldiery hurling lances from the vessels against the creatures when they leapt up alongside'. This makes navigiis an ablative of the phrase e navigiis and adsultantibus a dative referring to unspecified plural things (which they then make 'creatures' although we're only talking about one whale). Pliny is not an elegant writer, but he surely wouldn't write such a confusing sentence.]

Translation: Bill Thayer.
IX,xxix,62-63 - Nunc principatus scaro datur, qui solus piscium dicitur ruminare herbisque vesci atque non aliis piscibus, Carpathio maxime mari frequens. promunturium Troadis Lectum numquam sponte transit. inde advectos Tiberio Claudio principe Optatus e libertis eius praefectus classis inter Ostiensem et Campaniae oram sparsos disseminavit, quinquennio fere cura adhibitia, ut capti redderentur mari. postea frequentes inveniuntur Italiae litore, non antea ibi capti, admovetque sibi gula sapores piscibus satis et novum incolam mari dedit, ne quis peregrinas aves Romae parere miretur. IX,xxix,62-63 - 'Nowadays the wrasse is felt to be the best fish (it is said to be alone among fish in chewing a cud and eating grasses rather than other fish); it is particularly common in the Carpathian Sea: never does it range of its own accord beyond Lectum in the Troad. From there, in the reign of Tiberius Claudius, Optatus, one of his freedmen who was commander of a fleet, seeded them between the Ostian and the Campanian mouths, taking care for about five years to throw back to the sea any that were caught. Since then they have been frequently found off the shores of Italy, when they'd never been caught there before; thus gluttony has provided itself with some fresh flavors by sowing fish, and has given the sea a new inhabitant: no great wonder, then, that foreign birds [as well] breed at Rome.'

Translation: Bill Thayer.
XIV.viii.61 - Divus Augustus Setinum praetulit cunctis et fere secuti principes, confessa propter experimenta, non temere cruditatibus noxiis ab ea saliva. nascitur supra Forum Appi. antea Caecubo erat generositas celeberrima in palustribus populetis sinu Amynclano, quod iam intercidit incuria coloni locique angustia, magis tamen fossa Neronis, quam a Baiano lacu Ostiam usque navigabilem incohaverat. XIV.viii.61 - 'Augustus of blessed memory preferred Setinum [wine] to all the others as did almost all the other emperors after him, due to experience: you need not fear that a taste for it might give you stomach reflux. It grows on the heights above Forum Appii. Before that, the wine most famous for its quality was the Caecuban, growing in poplar thickets in the marshes on the Bay of Amynclae: the vineyard has died off due to the grower's neglect and the small acreage, more yet in fact because of the canal that Nero started, providing a navigable link from the lake of Baiae to Ostia.'

[Loeb has a slightly different Latin text]

Translation: Bill Thayer.
XV.xxvii.97 - minimum in hac arbore ingenia profecerunt, nec nominibus nec insitis; nec alio modo quam pomi magnitudine differunt mora Ostiensia et Tusculana Romae. XV.xxvii.97 - '[speaking of the mulberry tree:] Very few improvements have been made to this tree, whether in cultivars or in grafting; and other than in size, there is no difference between the Ostia and Tusculanum mulberry and the one found at Rome.

[Loeb has a different Latin text]

Translation: Bill Thayer.
XVI,lxxvi,201-2 - abies admirationis praecipuae visa est in nave, quae ex Aegypto Gai principis iussu obeliscum in Vaticano circo statutum quattuorque truncos lapidis eiusdem ad sustinendum eum adduxit. qua nave nihil admirabilius visum in mari certum est. CXX modium lentis pro saburra ei fuere. longitudo spatium obtinuit magna ex parte Ostiensis portus latere laevo. ibi namque demersa est Claudio principe cum tribus molibus turrium altitudine in ea exaedificatis obiter Puteolano pulvere advectisque. arboris eius crassitudo quattuor hominum ulnas conplectentium implebat. XVI,lxxvi,201-2 - An especially wonderful fir was seen in the ship which brought from Egypt at the order of the emperor Gaius the obelisk erected in the Vatican circus and four shafts of the same stone to serve as its base. It is certain that nothing more wonderful than this ship has ever been seen on the sea: it carried one hundred and twenty bushels of lentils for the ballast, and its length took up a large part of the left side of the harbour of Ostia, for under the emperor Claudius it was sunk there, with three moles as high as towers erected upon it that had been made of Pozzuoli cement for the purpose and conveyed to the place. It took four men to span the girth of this tree with their arms.

Translation: Loeb, Rackham.
XXXVI,xiv,70 - divus Claudius aliquot per annos adservatam, qua C. Caesar inportaverat, omnibus quae umquam in mari visa sunt mirabiliorem, in ipsa turribus Puteolis e pulvere exaedificatis, perductam Ostiam portus gratia mersit. XXXVI,xiv,70 - The ship used by the emperor Gaius for bringing a third [obelisk] was carefully preserved for several years by Claudius of Revered Memory, for it was the most amazing thing that had ever been seen at sea. The caissons made of cement were erected in its hull at Pozzuoli; whereupon it was towed to Ostia and sunk there by order of the emperor, so to contribute to his harbour-works.

Translation: Loeb, Eicholz.
XXXVI,xviii,83 - Magnificatur et alia turris a rege facta in insula Pharo portum optinente Alexandriae, quam constitisse DCCC talentis tradunt, magno animo, ne quid omittamus, Ptolemaei regis, quo in ea permiserit Sostrati Cnidi architecti structura ipsa nomen inscribi. usus eius nocturno navium cursu ignes ostendere ad praenuntianda vada portusque introitum, quales iam compluribus locis flagrant, sicut Ostiae ac Ravennae. periculum in continuatione ignium, ne sidus existimeretur, quoniam e longinquo similis flammarum aspectus est. XXXVI,xviii,83 - Another towering structure built by a king is also extolled, namely the one that stands on Pharos, the island that commands the harbour at Alexandria. The tower is said to have cost 800 talents. We should not fail to mention the generous spirit shown by King Ptolemy, whereby he allowed the name of the architect, Sostratus of Cnidos, to be inscribed on the very fabric of the building. It serves, in connection with the movements of ships at night, to show a beacon so as to give warning of shoals and indicate the entrance to the harbour. Similar beacons now burn brightly in several places, for instance at Ostia and Ravenna. The danger lies in the uninterrupted burning of the beacon, in case it should be mistaken for a star, the appearance of the fire from a distance being similar.

Translation: Loeb.