Transporting the Vatican Obelisk

'Eight suggested methods for raising the obelisk'

'Descrittione della forma del castello fatto per alzare la guglia'

'La pianta, e compartimento di tutti gli argani
con tutte le preparationi fatte per calar la guglia'

'La gvglia dentro al castello, nel modo che stava mentre calaua à basso'

'La gvglia per la punta, subito che fu colcata sopra lo
strascino, con tvtte le corde, che la sostentavano dentro al
castello fermato con ventole da tramontana, e ostro.'

'La pianta, e compartimento di tutti gli argani con tutte le
preparationi fatte per calar la gvglia, come s'è detto di sopra'

'Douendosi condur la guglia da questo lugo, sino su a la piazza
San Pietro per distanza di canne cento quindici, e iui drizzarla..'

'Monte armato a torno il castello, che gli sorgeva sopra per drizzar la guglia..'

'Tre guglie in piedi per poter mostrare in vna vista
l'attaccatura delle traglie in tutte tre le facie sudette'

'Il castello aperto in faccia, con la pvnta della gvglia
tiratavi dentro, e i canapi, che la sostentauano.'

'Della trasportatione dell'obelisco vaticano et delle
fabriche di nostro signore papa Sisto V fatte dal cavallier
Domenico Fontana, architetto di Sva Santita, libro primo.'

Guglia con i suoi adornamenti posta nel mezo della piazza;
Fabrica della chiesa di San Pietro nel modo, che starà, quando sarà finita..'

'Il palazzo fatto nella vigna di nostro signore mentre era cardinale.'

'La Capella del Presepio.'

'Il grand'obelisco di Costantio a S. Giouanni Laterano.'

'La gvglia della Madonna del Populo - faccia uerso tramontana,
faccia uerso oriente, faccia uerso mezzogiorno, faccia uerso occidente;
Colonna Antonnia ; Colonna Traiana'

'Questo è il disegno del tabernacolo di metallo dorato à fuoco
per il Santissimo Sacramento collocato su l'altare posto sopra
il Presepio di Christo nostro Red.re. nella capella di N. Sig.re...'

An 83 feet tall, 320 ton granite obelisk was brought by Caligula from Alexandria in Egypt to Rome aboard the largest ship ever built in ~37AD. It is reported that the ship - a barge - was later sunk on purpose to provide a foundation for a quay in the port of Ostia.

The obelisk - which folklore alleges contained the ashes of Julius Caesar in its metal crowning orb - was somehow erected by Caligula in the famed Circus Maximus.

During the renaissance, long after the Circus Maximus arena had disappeared, the monumental St Peters Basilica construction project, headed by Michelangelo and Giacomo Della Porta, was undertaken at the direction of a number of Popes. The idea of moving the obelisk a quarter of a mile to a place in front of the basilica was raised on several occasions but even Michelangelo declined to believe it was feasible.

Pope Sixtus V was insistent however, and in 1585 invited engineering proposals for carrying out the move. He was apparently persuaded to accept the submission of Domenico Fontana (one of the architectural engineers working under Della Porta) when a model of the engineering system allowed Sixtus to turn winches and successfully move the miniature version of the obelisk himself.

Fontana's project didn't introduce any new engineering techniques but the size and nature of the problem ensured it would be remembered as one of the most amazing technological feats of the 16th century. Reports vary but it seems the move took around 12 months in total to complete; half of the time being spent on scaffold construction and clearing buildings from the area. "The scaffold was operated with tuned precision by 900 men and 74 horses, harmoniously arranged amidst a myriad of pulleys, levers, and capstans".

The obelisk was exorcised, the (ashless, as Fontana advises) orb was replaced by a christian cross and it was erected at its present location on September 14, 1586 before a large crowd who were silenced by the Swiss guard.

• Domenico Fontana published 'Della Trasportatione dell’Obelisco Vaticano et delle Fabriche di Nostro Signore Papa Sisto V', which includes a large number of detailed copperplate etchings by Natale Bonifacio, in 1590. There are a few copies online. I chose to snag images from the copy online at the Portuguese National Library because they are by far the largest versions. I brightened all the above images slightly. It's perhaps personal taste as to whether that style of image is better or worse aesthetically speaking than the collection of illustrations available at NYPL (thumbnails). But NYPL is the quickest and easiest way to view all the illustrations [all of the image captions above were copied from NYPL] Octavo also has the complete book available and you can just about read the text if you squint.
• The Saint Peters Basilica site has an extensive history section.
• 'A Forest of Obelisks' by Paul Lunde at Saudi Aramco World.
• 'Obelisci' from Bill Sayer's site.
• Domenico Fontana at the Catholic Encyclopedia.
• The short quote above comes from an extensive but thoroughly interesting Masters thesis by Eric Solomon Toker from 1998 entitled: 'An Architectural Excursis into the Site of Becoming: Domenico Fontana's Della Trasportatione dell'Obelisco Vaticano'. It also includes an english translation of the first chapter as an appendix - an english version was never produced - which is an obsequious yet self praising slab of amusing text. The catch? It is an 8.5 Mb pdf document. [via Facetation]
• Although slightly tangential, 'Kircher's Obelisks' is very interesting.
• 'How obelisks got where they are now' (excerpt) from the Newcomen Society.
• 'Obelisks' from a site at Australian National University.
• 'Moving an Obelisk' or 'Moving the Vatican Obelisk' - for quick versions.