Ask around for what every­one knows about Istan­bul (oth­er than that it used to be called Con­stan­tino­ple), and you’ll find that the pres­ence of Hagia Sophia there comes right to many a mind. Less like­ly to be men­tioned is its prone­ness to earth­quakes, though it tends to rank just below Tokyo on lists of cities under the great­est threat from fault lines below. These two char­ac­ter­is­tics turn out to have a con­nec­tion, man­i­fest in the ongo­ing seis­mic retro­fitting of Istan­bul’s sym­bol­ic cathe­dral-turned-mosque-turned-muse­um turned-mosque-again. Hagia Sophia is one of the most cel­e­brat­ed reli­gious build­ings stand­ing; keep­ing it that way requires a seri­ous engi­neer­ing effort, as explained in the new B1M video above.

Since it was first built in the fourth cen­tu­ry, Hagia Sophia has actu­al­ly sus­tained severe earth­quake dam­age quite a few times, includ­ing a com­plete col­lapse of its cupo­la in the year 558 and par­tial col­laps­es in the tenth and four­teenth cen­turies. The con­struc­tion of its famous cen­tral dome, along with the small­er sub-domes that sup­port it, gets a sec­tion of its own in the video.

Host Fred Mills also gives due men­tion to the eight green mar­ble columns that sup­port the upper floors of the cathe­dral, thought to have been recy­cled from the ruins of the Tem­ple of Artemis (one of the Sev­en Won­ders of the Ancient World), and the red stone set into the floor on which emper­ors were once crowned that would have been brought in from the Egypt­ian desert.

In these and oth­er respects, Hagia Sophia isn’t just a site of pil­grim­age and wor­ship, but also a ver­i­ta­ble built record of cen­turies upon cen­turies of Roman, Greek, Chris­t­ian, and Islam­ic civ­i­liza­tion. As evi­denced by the scaf­fold­ing cur­rent­ly up to facil­i­tate the project of ready­ing it for the inevitable com­ing of the big one — or rather, the big­ger one — the struc­ture con­tin­ues to change with time, though our era has an espe­cial­ly strong con­cern for pre­serv­ing what have by now become his­tor­i­cal fea­tures. Hence the efforts now being put into restora­tion: of the dome, nat­u­ral­ly, but also of the floors, columns, and mosaics. If all goes well, Hagia Sophia will con­tin­ue to stand as the most strik­ing struc­ture in Istan­bul’s already dra­mat­ic urban and geo­graph­i­cal set­ting for anoth­er mil­len­ni­um and a half, incor­po­rat­ing his­to­ry all the while.

Relat­ed con­tent:

An Intro­duc­tion to Hagia Sophia: After 85 Years as a Muse­um, It’s Set to Become a Mosque Again

How the Byzan­tine Empire Rose, Fell, and Cre­at­ed the Glo­ri­ous Hagia Sophia: A His­to­ry in Ten Ani­mat­ed Min­utes

A Cul­tur­al Tour of Istan­bul, Where the Art and His­to­ry of Three Great Empires Come Togeth­er

360 Degree Vir­tu­al Tours of the Hagia Sophia

Hear the Hagia Sophia’s Awe-Inspir­ing Acoustics Get Recre­at­ed with Com­put­er Sim­u­la­tions, and Let Your­self Get Trans­port­ed Back to the Mid­dle Ages

Istan­bul Cap­tured in Beau­ti­ful Col­or Images from 1890: The Hagia Sophia, Top­ka­ki Palace’s Impe­r­i­al Gate & More

Based in Seoul, Col­in Marshall writes and broad­casts on cities, lan­guage, and cul­ture. He’s the author of the newslet­ter Books on Cities as well as the books 한국 요약 금지 (No Sum­ma­riz­ing Korea) and Kore­an Newtro. Fol­low him on the social net­work for­mer­ly known as Twit­ter at @colinmarshall.

Since it was first built as a Myce­naean fortress in the thir­teenth cen­tu­ry BC, what we now know as the Acrop­o­lis has been used to wor­ship not just Greek gods, but also, in lat­er peri­ods, the Vir­gin Mary and Allah. Now, of course, with its days of mil­i­tary and reli­gious func­tions long behind it, it stands as a set of ruins. Still, they’re very pop­u­lar ruins, as evi­denced by the crowds cap­tured in the video above from Manuel Bra­vo. Though most tourists at the Acrop­o­lis come with the idea that its build­ings would have looked more glo­ri­ous in the dis­tant past, few can have much of a sense of how to imag­ine that with any accu­ra­cy. Using 3D mod­els, Bra­vo inte­grates views of how the Parthenon, the Tem­ple of Athena Nike, and oth­er struc­tures look now with how they would have looked in Athens’ gold­en age.

To ful­ly appre­ci­ate the Acrop­o­lis requires not just an idea of how it was orig­i­nal­ly intend­ed to look, as Bra­vo empha­sizes, but also the inten­tions of ancient Greek archi­tec­ture. The approach up the hill was meant to feel like an ascent from the mun­dane world into the sacred one.

Enter­ing the cen­tral space on top, the vis­i­tor was led to view­ing points that showed the sur­round­ing col­lec­tion of build­ings at their most dra­mat­ic, a design the archi­tects might have described as cin­e­mat­ic, had cin­e­ma exist­ed at the time. Even in its ruined state, the Acrop­o­lis still trans­mits a sense of how, where, and to what degree that vis­i­tor was meant to be filled with awe, as well as where he was meant to look. And noth­ing up there — at least in the absence of Phidias’ thir­ty-foot stat­ue Athena Pro­ma­chos — draws atten­tion as delib­er­ate­ly as the Parthenon.

As we pre­vi­ous­ly not­ed here on Open Cul­ture, if you make the trip to the Acrop­o­lis your­self, you can now see the Parthenon with­out scaf­fold­ing (or, depend­ing on when you go, a min­i­mum of scaf­fold­ing) for the first time in 200 years. That lack of obstruc­tion makes it eas­i­er to envi­sion the glo­ries of that cel­e­brat­ed build­ing back when it was both the tem­ple of Athena and the trea­sury of Athens. But as Bra­vo says, if you real­ly want to gaze upon the Parthenon as the ancients knew it, mar­bles and all, you’ll have to make the trek out to Nashville, Ten­nessee, where a full-scale repli­ca was built in 1897 for the city’s Cen­ten­ni­al Expo­si­tion. It may feel a bit odd to turn up in a place known for coun­try music and bach­e­lorette par­ties in search of the archi­tec­tur­al, and per­haps spir­i­tu­al foun­da­tion of Europe. But then, civ­i­liza­tion has nev­er tak­en a pre­dictable course.

Relat­ed Con­tent:

How the Ancient Greeks Built Their Mag­nif­i­cent Tem­ples: The Art of Ancient Engi­neer­ing

A 3D Mod­el Reveals What the Parthenon and Its Inte­ri­or Looked Like 2,500 Years Ago

A Vir­tu­al Tour of Ancient Athens: Fly Over Clas­si­cal Greek Civ­i­liza­tion in All Its Glo­ry

The City of Nashville Built a Full-Scale Repli­ca of the Parthenon in 1897, and It’s Still Stand­ing Today

How the World’s Biggest Dome Was Built: The Sto­ry of Fil­ip­po Brunelleschi and the Duo­mo in Flo­rence

Take a High Def, Guid­ed Tour of Pom­peii

Based in Seoul, Col­in Marshall writes and broad­casts on cities, lan­guage, and cul­ture. He’s the author of the newslet­ter Books on Cities as well as the books 한국 요약 금지 (No Sum­ma­riz­ing Korea) and Kore­an Newtro. Fol­low him on the social net­work for­mer­ly known as Twit­ter at @colinmarshall.

When we think of mod­ern archi­tec­ture, we often think first of what’s called the Inter­na­tion­al Style, whose min­i­mal­ist, rec­ti­lin­ear, dec­o­ra­tion-free forms were cham­pi­oned by the likes of Wal­ter Gropius, Lud­wig Mies van der Rohe, and Le Cor­busier. Though they did build projects all over the world, that isn’t exact­ly the rea­son for the name. In fact, the Inter­na­tion­al Style rep­re­sents an attempt to devel­op a cul­tur­al­ly neu­tral aes­thet­ic for all built envi­ron­ments, deploy­able equal­ly in Europe, Asia, the Amer­i­c­as, and every­where else besides. That pre­tense to uni­ver­sal­i­ty may count as the most utopi­an aspect of an avowed­ly utopi­an move­ment — and the one whose imprac­ti­cal­i­ty came soon­est to light.

Before he became Brazil’s most famous archi­tect, Oscar Niemey­er sub­scribed to the prin­ci­ples of the Inter­na­tion­al Style. But then, as an acolyte of Le Cor­busier, he could hard­ly have done oth­er­wise. When the great man came to Rio de Janeiro in 1936 to design the new Min­istry of Edu­ca­tion and Health, Niemey­er was hired to work on the project.

The expe­ri­ence seems to have done its part to con­vince him that the Inter­na­tion­al Style was­n’t as inter­na­tion­al as all that, and fur­ther­more, that its rigid dic­tates would have to be bent to suit his home­land. This bend­ing would, in a sense, be lit­er­al: like Frank Gehry or Zaha Hadid after him, Niemey­er devot­ed his archi­tec­ture to the pur­suit of the curve, inspired by exam­ples seen in every­thing from the moun­tains of Brazil’s land­scape to the bod­ies of its women.

In 1956, the new­ly elect­ed pres­i­dent Jusceli­no Kubitschek imme­di­ate­ly real­ized the plan, writ­ten into the coun­try’s con­sti­tu­tion long before, of build­ing a new cen­tral city to relieve Rio of its sta­tus as the cap­i­tal. Chris­tened Brasília, it was to be con­struct­ed on a vast, emp­ty plateau entire­ly along ratio­nal, mod­ernist guide­lines, with defined dis­tricts orga­nized along a cru­ci­form city plan often likened to a bird or an air­plane and mon­u­men­tal struc­tures meant to project a for­ward-look­ing image. Niemey­er was select­ed to design those struc­tures, which imme­di­ate­ly became ele­ments of the city’s visu­al sig­na­ture upon its inau­gu­ra­tion in 1960: ever since, sel­dom has a pho­to­graph failed to include the twin tow­ers and domes of his Nation­al Con­gress or the Space-Age crown of thorns atop his Cathe­dral of Brasília.

The both admin­is­tra­tive and oth­er­world­ly form of cen­tral Brasília remains allur­ing, though the city itself began draw­ing crit­i­cism even before its com­ple­tion. “This is what you get when per­fect­ly decent, intel­li­gent and tal­ent­ed men start think­ing in terms of space, rather than place, and about sin­gle rather than mul­ti­ple mean­ings,” declared a frown­ing Robert Hugh­es in his 1980 TV series The Shock of the New. “It’s what you get when you design for polit­i­cal aspi­ra­tions and not real human needs. You get miles of jer­ry-built pla­ton­ic nowhere infest­ed with Volk­swa­gens.” Indeed, the dom­i­na­tion of car infra­struc­ture and strict sep­a­ra­tion of func­tions hard­ly proved con­ducive to the spon­ta­neous, con­vivial aspects of Brazil­ian life. But res­i­dents and vis­i­tors alike tend to report that Brasíli­a’s urban design has been improved as its pop­u­la­tion has grown, and mas­sive­ly, with com­men­su­rate improve­ments to its qual­i­ty of life over the decades. It may not inspire many bossa nova songs, but the cap­i­tal nev­er­the­less reflects a gen­uine facet of what Brazil is — and what it once dreamed of becom­ing.

Relat­ed Con­tent:

A is for Archi­tec­ture: 1960 Doc­u­men­tary on Why We Build, from the Ancient Greeks to Mod­ern Times

Leonar­do da Vin­ci Designs the Ide­al City: See 3D Mod­els of His Rad­i­cal Design

Why Dutch & Japan­ese Cities Are Insane­ly Well Designed (and Amer­i­can Cities Are Ter­ri­bly Designed)

Frank Lloyd Wright Designs an Urban Utopia: See His Hand-Drawn Sketch­es of Broad­acre City (1932)

The World Accord­ing to Le Cor­busier: An Ani­mat­ed Intro­duc­tion to the Most Mod­ern of All Archi­tects

Take a Vir­tu­al Tour of Brazil’s Nation­al Muse­um & Its Arti­facts: Google Dig­i­tized the Museum’s Col­lec­tion Before the Fate­ful Fire

Based in Seoul, Col­in Marshall writes and broad­casts on cities, lan­guage, and cul­ture. He’s the author of the newslet­ter Books on Cities as well as the books 한국 요약 금지 (No Sum­ma­riz­ing Korea) and Kore­an Newtro. Fol­low him on the social net­work for­mer­ly known as Twit­ter at @colinmarshall.

Very few of us have ever set foot near a gen­uine medieval cas­tle, espe­cial­ly if we don’t hap­pen to live in Europe. Yet prac­ti­cal­ly all of us still, here in the twen­ty-first cen­tu­ry, refer with some fre­quen­cy to their com­po­nents in our every­day speech. When we invoke moats, draw­bridges, dun­geons, and even cat­a­pults, we almost always do so metaphor­i­cal­ly — assum­ing we’re not active mem­bers of a his­tor­i­cal re-cre­ation soci­ety — yet we also have no prob­lem see­ing them before our mind’s eye with what feels like per­fect clar­i­ty. The dif­fi­cul­ty comes if we attempt to inte­grate all of those images, absorbed hap­haz­ard­ly from folk tales and pop­u­lar cul­ture, into a func­tion­ing whole.

The fact of the mat­ter is that peo­ple in the Mid­dle Ages real­ly did live and work in cas­tles, and occa­sion­al­ly had to defend them, or indeed attack them. Using a 3D-ren­dered repli­ca con­struct­ed to reflect how those struc­tures were built in the frag­ment­ed Europe of the eleventh through four­teenth cen­turies after the fall of the Car­olin­gian Empire, the Decon­struct­ed video above explains every­thing about how they worked in the span of about twen­ty min­utes.

This tour begins with the bar­bi­can: not the cel­e­brat­ed Bru­tal­ist com­plex in Lon­don, but the exte­ri­or for­ti­fied pas­sage “designed to expose attack­ers to defen­sive fire before they even reach the main gate.” And it only gets hard­er for would-be cas­tle cap­tors from there.

Para­pets with cutouts through which archers could fire their arrows, the moat that made under­min­ing (a term com­mon enough in mod­ern lan­guage that few now rec­og­nize its ori­gins) next to impos­si­ble, the draw­bridge that could be pulled up, the walls slant­ed to repel bat­ter­ing rams, the spiked portcullis­es that could be slammed down: these are just a few of the myr­i­ad defens­es that made invaders’ lives dif­fi­cult — and, in many cas­es, short, espe­cial­ly when “mur­der holes” were involved. (Now there’s a term just wait­ing for inclu­sion in our lex­i­con.) The exam­ple con­struct­ed here rep­re­sents the zenith of cas­tle design, the cul­mi­na­tion of an evo­lu­tion­ary process that began in the tenth cen­tu­ry with a struc­ture called the motte and bai­ley: a term that, if you don’t already know it from oth­er con­texts, you prob­a­bly just don’t do enough ver­bal bat­tle on the inter­net.

Relat­ed Con­tent:

How To Build a 13th-Cen­tu­ry Cas­tle, Using Only Authen­tic Medieval Tools & Tech­niques

Behold a 21st-Cen­tu­ry Medieval Cas­tle Being Built with Only Tools & Mate­ri­als from the Mid­dle Ages

The Tech­nol­o­gy That Brought Down Medieval Cas­tles and Changed the Mid­dle Ages

How Medieval Cathe­drals Were Built With­out Sci­ence, or Even Math­e­mat­ics

The Roman Colos­se­um Decon­struct­ed: 3D Ani­ma­tion Reveals the Hid­den Tech­nol­o­gy That Pow­ered Rome’s Great Are­na

Based in Seoul, Col­in Marshall writes and broad­casts on cities, lan­guage, and cul­ture. He’s the author of the newslet­ter Books on Cities as well as the books 한국 요약 금지 (No Sum­ma­riz­ing Korea) and Kore­an Newtro. Fol­low him on the social net­work for­mer­ly known as Twit­ter at @colinmarshall.