{{Short description|Spa town and frazione in Emilia-Romagna, Italy}} {{Use dmy dates|date=April 2026}} {{Infobox Italian frazione | name = Porretta Terme | comune = Alto Reno Terme | native_name = Puràtta | image_skyline = Porretta_Terme_-_panorama_180%C2%B0.jpg | image_caption = View of Porretta Terme | coordinates = {{coord|44|9|37|N|10|58|24|E|display=inline,title}} | region = [[Emilia-Romagna]] | province = [[Metropolitan City of Bologna|Bologna]] (BO) | elevation_m = 349 | saint = [[Mary Magdalene]] | day = 22 July | postal_code = 40046 | area_code = 0534 }}
'''Porretta Terme''' ([[Bolognese dialect|Bolognese]]: ''Puràtta'') is a spa town and ''[[frazione]]'' of the ''[[comune]]'' of [[Alto Reno Terme]], in the [[Metropolitan City of Bologna]], [[Emilia-Romagna]], northern Italy. It lies in the upper valley of the [[Reno (river)|Reno]], in the [[Tuscan-Emilian Apennines]], near the border with [[Tuscany]].
Known since Roman times for its thermal springs, Porretta developed into one of the historic spa towns of northern Italy.<ref name="TreccaniPorretta">{{cite web |title=Porretta Terme |url=https://www.treccani.it/enciclopedia/porretta-terme_%28Enciclopedia-Italiana%29/ |website=Treccani |publisher=Istituto dell'Enciclopedia Italiana |language=it |access-date=28 April 2026}}</ref><ref name="TermeAlteMiC">{{cite web |title=Terme Alte |url=https://beniabbandonati.cultura.gov.it/beni/terme-alte/ |website=Beni culturali abbandonati |publisher=Ministero della Cultura |language=it |access-date=28 April 2026}}</ref> It was an independent municipality until 31 December 2015, when it merged with [[Granaglione]] to form the new municipality of Alto Reno Terme.<ref name="LR19">{{cite web |title=Legge regionale 23 novembre 2015, n. 19: Istituzione del Comune di Alto Reno Terme mediante fusione dei Comuni di Granaglione e Porretta Terme |url=https://demetra.regione.emilia-romagna.it/al/articolo?urn=er:assemblealegislativa:legge:2015;19 |website=Demetra |publisher=Regione Emilia-Romagna |language=it |access-date=28 April 2026}}</ref>
Although administratively Porretta Terme is a ''frazione'' of Alto Reno Terme, the built-up area of Porretta is continuous with neighbouring settlements across the Reno valley floor. On the right bank of the Reno, Berzantina belongs administratively to the municipality of [[Castel di Casio]], while remaining closely connected with Porretta in the local geography of the valley.<ref name="RadioCorriere">{{cite web |title=Porretta Terme - BO |url=https://www.radiocorriere.net/emilia_romagna/Porretta_Terme_Bo.html |website=Radiocorriere |language=it |access-date=28 April 2026}}</ref><ref name="ICBerzantina">{{cite web |title=Infanzia Casola Berzantina |url=https://icporretta.edu.it/struttura/infanzia-casola-berzantina/ |website=Istituto Comprensivo Porretta Terme |language=it |access-date=28 April 2026}}</ref>
== Geography == Porretta Terme is situated at about {{convert|349|m|ft|abbr=on}} above sea level, at the confluence of the Rio Maggiore with the Reno. The older settlement developed along the Rio Maggiore, while later expansion followed the Reno valley floor, the Porrettana road and the railway.
The settlement lies in the upper Reno valley, a narrow Apennine corridor linking the Bolognese area with the Pistoia mountains and northern Tuscany. The Porrettana railway marks an important physical and administrative division in the valley floor, separating Porretta from Berzantina, which is situated on the right bank of the Reno in the municipality of Castel di Casio.<ref name="RadioCorriere" />
== History == The history of Porretta is closely linked to its mineral waters. The springs were known and used in antiquity, and the historic spa area developed along the upper course of the Rio Maggiore. Roman archaeological finds discovered in the area of the Terme Alte attest to the ancient use of the site.<ref name="TermeAlteMiC" />
The town was formerly known as ''Bagni della Porretta'', a name referring directly to the baths and thermal waters.<ref name="TreccaniBagni">{{cite web |title=Bagni della Porretta |url=https://www.treccani.it/enciclopedia/bagni-della-porretta_%28Enciclopedia-Italiana%29/ |website=Treccani |publisher=Istituto dell'Enciclopedia Italiana |language=it |access-date=28 April 2026}}</ref> During the nineteenth century, the development of spa facilities and the opening of the [[Pistoia–Bologna railway|Porrettana railway]] strengthened Porretta's role as a thermal and mountain resort.
During the [[Italian Campaign (World War II)|Italian campaign]] of [[World War II]], Porretta lay near the [[Gothic Line]] front. The town housed the headquarters of the [[Brazilian Expeditionary Force|1st Brazilian Expeditionary Division]] between November 1944 and the final Allied breakthrough of the Gothic Line.<ref>{{cite book |last=Oliveira |first=Frank Marcio de |title=Attaché Extraordinaire: Vernon A. Walters in Brazil |publisher=National Defense Intelligence College |year=2010 |isbn=9781932946222 |pages=10–11}}</ref>
On 1 January 2016 the former municipalities of Porretta Terme and Granaglione were abolished and merged into the new municipality of Alto Reno Terme, established by Regional Law no. 19 of 23 November 2015.<ref name="LR19" />
== Thermal springs == Porretta Terme is one of the historic spa towns of the northern Apennines. Treccani describes its mineral waters as chlorinated-sodium iodinated and chlorinated-sodium sulphurous thermal waters, with temperatures historically reported between {{convert|29|C|F|abbr=on}} and {{convert|38|C|F|abbr=on}}.<ref name="TreccaniPorretta" />
The historic upper spa complex, known as the Terme Alte, is located along the Rio Maggiore, below Monte della Croce. The complex includes several historic spa buildings and preserves evidence of the long continuity of thermal use in the town.<ref name="TermeAlteMiC" />
Modern geochemical studies distinguish the Terme Alte springs from the Puzzola group, near the Reno river. The thermal waters are mainly of Na–Cl–HCO<sub>3</sub> composition and are interpreted as meteoric waters that circulate deeply through Apennine geological formations before rising to the surface.<ref name="Tassi2022">{{cite journal |last1=Tassi |first1=Franco |last2=Garofalo |first2=Paolo S. |last3=Turchetti |first3=Filippo |last4=De Santis |first4=Davide |last5=Capecchiacci |first5=Francesco |last6=Vaselli |first6=Orlando |last7=Cabassi |first7=Jacopo |last8=Venturi |first8=Stefania |last9=Vannini |first9=Stefano |title=Insights into the Porretta Terme (northern Apennines, Italy) hydrothermal system revealed by geochemical data on presently discharging thermal waters and paleofluids |journal=Environmental Geochemistry and Health |volume=44 |pages=1925–1948 |year=2022 |doi=10.1007/s10653-020-00762-5 |doi-access=free|pmc=9177482 }}</ref>
== Geology and mineralogy == Porretta is also known for its quartz and calcite mineralizations. The University of Bologna's Luigi Bombicci Mineralogical Collection describes the local ''quarzo aeroidro a tramogge'', or enhydro hopper quartz, as notable for the large size of its crystals and crystal aggregates.<ref name="UniboQuartz">{{cite web |title=Il quarzo e la calcite di Porretta |url=https://sma.unibo.it/it/il-sistema-museale/collezione-di-mineralogia-luigi-bombicci/collezioni-1/il-quarzo-e-la-calcite-di-porretta |website=Sistema Museale di Ateneo |publisher=Università di Bologna |language=it |access-date=28 April 2026}}</ref>
Hopper quartz crystals have a stepped morphology caused by faster growth along the crystal edges than in the centre of the crystal faces. Some crystals are enhydro, containing internal cavities with fossil hydrothermal water and methane bubbles.<ref name="UniboQuartz" /> These mineralizations are linked to the deep hydrothermal system associated with the thermal waters of Porretta.<ref name="Tassi2022" />
The regional geosite inventory of Emilia-Romagna records the Porretta quartz occurrences among the geological features of the area, noting the typical hopper habit of the crystals.<ref name="GeositiQuartz">{{cite web |title=I Geositi dell'Emilia-Romagna: quarzo di Porretta |url=https://geo.regione.emilia-romagna.it/schede/geositi/scheda.jsp?id=185 |publisher=Regione Emilia-Romagna |language=it |access-date=28 April 2026}}</ref> The private Agostini Mineralogical Collection is listed at Ca' Giannini, in the municipality of Alto Reno Terme.<ref name="AgostiniCollection">{{cite web |title=Collezione mineralogica privata Agostini |url=https://www.localshop24.com/it/alto-reno-terme-bo-it/attivita/museo/collezione-mineralogica-privata-agostini/ |website=LocalShop24 |language=it |access-date=5 May 2026}}</ref>
== Main sights == === Terme Alte and Grottino Chini === The Terme Alte form the historic upper spa complex of Porretta. Inside the complex is the ''Grottino Chini'', also known as the Sala Bibita, a small drinking hall decorated with ceramic works by [[Galileo Chini]], one of the leading figures of Italian [[Art Nouveau]] decoration.<ref name="TermeAlteMiC" /><ref name="GrottinoChini">{{cite web |title=Il Grottino Chini di Porretta |url=https://www.discoveraltorenoterme.it/il-grottino-chini-di-porretta/ |website=Discover Alto Reno Terme |language=it |access-date=28 April 2026}}</ref>
=== Religious buildings === The parish church of Santa Maria Maddalena stands in the historic centre of Porretta. The present building was constructed between 1690 and 1696, replacing an older church of medieval origin.<ref name="SantaMaddalena">{{cite web |title=Chiesa di Santa Maria Maddalena - Alto Reno Terme |url=https://www.tourer.it/scheda?chiesa-di-santa-maria-maddalena-alto-reno-terme= |website=Tourer.it |publisher=Segretariato regionale del Ministero della Cultura per l'Emilia-Romagna |language=it |access-date=28 April 2026}}</ref>
The Sanctuary of the Madonna del Ponte is located near the Reno, along the road towards Ponte della Venturina and Pistoia.<ref name="MadonnaPonte">{{cite web |title=The sanctuary of Madonna del Ponte |url=https://www.discoveraltorenoterme.it/the-sanctuary-of-madonna-del-ponte/ |website=Discover Alto Reno Terme |language=en |access-date=28 April 2026}}</ref> The Sanctuary of the Madonna del Faggio lies near Castelluccio, in the surrounding Apennine landscape.<ref name="MadonnaFaggio">{{cite web |title=Santuario della Madonna del Faggio |url=https://appenninobolognese.cittametropolitana.bo.it/it/luoghi/edifici-religiosi/santuario-della-madonna-del-faggio |website=Appennino Bolognese |publisher=Città metropolitana di Bologna |language=it |access-date=28 April 2026}}</ref>
== Culture == === Porretta Soul Festival === {{main|Porretta Soul Festival}}
Since 1988 Porretta has hosted the [[Porretta Soul Festival]], an annual festival dedicated to [[soul music]] and [[rhythm and blues]]. The festival was conceived by Graziano Uliani after he attended events in [[Macon, Georgia]], commemorating the twentieth anniversary of the death of [[Otis Redding]].<ref name="SoulHistory">{{cite web |title=History |url=https://porrettasoulfestival.it/en/history/ |website=Porretta Soul Festival |language=en |access-date=28 April 2026}}</ref>
=== Cinema === Porretta has a significant association with independent cinema. The ''Mostra Internazionale del Cinema Libero'' was founded in Porretta Terme in 1960 by figures including [[Cesare Zavattini]], Leonida Repaci, Bruno Grieco and Gian Paolo Testa.<ref name="CinemaLibero">{{cite web |title=Mostra Internazionale del Cinema Libero |url=https://porrettacinema.com/il-festival/mostra-internazionale-del-cinema-libero/ |website=Festival del Cinema di Porretta Terme |language=it |access-date=28 April 2026}}</ref> The present Festival del Cinema di Porretta Terme was founded in 2002 and presents itself as continuing that tradition.<ref name="PorrettaCinema">{{cite web |title=Il Festival |url=https://porrettacinema.com/il-festival/ |website=Festival del Cinema di Porretta Terme |language=it |access-date=28 April 2026}}</ref>
== Transport == Porretta Terme is served by [[Porretta Terme railway station]], on the [[Pistoia–Bologna railway]], commonly known as the Porrettana. The line, inaugurated in 1864, was the first railway connection across the Apennines between Tuscany and Emilia-Romagna and takes its name from Porretta.<ref name="VisitPistoiaRailway">{{cite web |title=Porrettana Railway |url=https://www.visitpistoia.eu/en/discover/ferrovia-porrettana/ferrovia-porrettana/ |website=Visit Pistoia |language=en |access-date=28 April 2026}}</ref><ref name="VisitTuscanyRailway">{{cite web |title=Discovering the mountains near Pistoia along the Porrettana Railway route |url=https://www.visittuscany.com/en/ideas/discovering-the-mountains-near-pistoia-along-the-porrettana-railway-route/ |website=Visit Tuscany |language=en |access-date=28 April 2026}}</ref>
The station is managed by [[Rete Ferroviaria Italiana]] and has four passenger tracks.<ref name="RFI">{{cite web |title=Porretta Terme |url=https://www.rfi.it/it/stazioni/porretta-terme.html |publisher=Rete Ferroviaria Italiana |language=it |access-date=28 April 2026}}</ref> The town is also crossed by the [[Strada statale 64 Porrettana]], the historic road route linking Bologna with Pistoia through the Reno valley.
== Former municipality == Until 31 December 2015 Porretta Terme was a separate municipality in the Province, later Metropolitan City, of Bologna. It included the hamlets of Capugnano, Castelluccio and Corvella and covered about {{convert|33.9|km2|sqmi|abbr=on}}.<ref name="FusionArea">{{cite web |title=Comuni interessati: Granaglione e Porretta Terme |url=https://www.assemblea.emr.it/fusione-di-comuni/mappa-delle-fusioni/granaglione-porretta/comuni-interessati |website=Assemblea legislativa |publisher=Regione Emilia-Romagna |language=it |access-date=28 April 2026}}</ref>
The municipality was abolished on 1 January 2016, when Porretta Terme and Granaglione were merged into the new municipality of Alto Reno Terme.<ref name="LR19" />
== See also == * [[Alto Reno Terme]] * [[Granaglione]] * [[Castel di Casio]] * [[Porretta Soul Festival]] * [[Pistoia–Bologna railway]] * [[Porretta Terme railway station]] * [[Reno (river)]] * [[Corno alle Scale]]
== References == {{Reflist}}
== External links == * {{Official website|https://www.comune.altorenoterme.bo.it/|Official website of Alto Reno Terme}} * [https://www.termediporretta.it/ Terme di Porretta] * [https://www.discoveraltorenoterme.it/porretta-terme-town/ Porretta Terme] at Discover Alto Reno Terme
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[[Category:Frazioni of the Metropolitan City of Bologna]] [[Category:Former municipalities of Emilia-Romagna]] [[Category:Spa towns in Italy]] [[Category:Hot springs of Italy]] [[Category:Alto Reno Terme]]