Bora-Hansgrohe’s Sam Bennett followed him home, while Trek-Segafredo’s Jasper Stuyven slotted into third.
The stage winner came from a considerable way back to finish with a clear margin ahead of the two.
The overall standings remained the same with Team Sunweb’s Tom Dumoulin retaining the maglia rosa and Movistar’s Nairo Quintana in second with Trek-Segafredo’s Bauke Mollema in third.
“It was difficult but thanks to my team we pulled it off and got another victory,” said Gaviria.
“Yes, I’m the Colombian with the most Giro stage wins but that doesn’t mean much. It means I prepared well for the Giro.”
The biggest news of the day was Geraint Thomas‘s exit from the race. The Team Sky rider has been suffering since his crash on stage nine and has lost time in each of the last two stages due to a knee injury.
He will now return to working for Chris Froome at the Tour de France but has vowed to return next year.
“Obviously it’s never nice to leave a race early, especially when it’s your main goal of the season, but I have to look at the bigger picture,” said Thomas.
“I’d love to continue, but it would be a case of trying to survive each day rather than racing.”
Top ten results
|1.||Fernando Gaviria (Quick-Step Floors)||3:47:45|
|2.||Sam Bennett (Bora-Hansgrohe)||"|
|3.||Jasper Stuyven (Trek-Segafredo)||"|
|4.||Roberto Ferrari (UAE Team Emirates)||"|
|5.||Ryan Gibbons (Dimension Data)||"|
|6.||Rüdiger Selig (Bora-Hansgrohe)||"|
|7.||Sacha Modolo (UAE Team Emirates)||"|
|8.||Caleb Ewan (Orica-Scott)||"|
|9.||André Greipel (Lotto Soudal)||"|
|10.||Viacheslav Kuznetsov (Katusha-Alpecin)||"|
|1.||Tom Dumoulin - Team Sunweb||56:28:53|
|2.||Nairo Quintana - Movistar Team||+2'23"|
|3.||Bauke Mollema - Trek-Segafredo||+2'38"|
|4.||Thibaut Pinot - FDJ||+2'40"|
|5.||Vincenzo Nibali - Bahrain-Merida||+2'47"|
|6.||Andrey Amador - Movistar Team||+3'05"|
|7.||Bob Jungels - Quick-Step Floors||+3'56"|
|8.||Domenico Pozzovivo (AG2R La Mondiale)||+3'59"|
|9.||Tanel Kangert (Astana Pro Team)||"|
|10.||Ilnur Zakarin - Katusha-Alpecin||+4'17"|
Full Stage 13 results