The 175.8km stage started and finished in the same seaside town, but there was plenty of drama in between as the peloton were forced to negotiate a hilly opening to the race.
Fatigue played a part in a sprint finish that reflected the difficulty of a day that had included six categorised climbs, with Bouhanni setting out for home a fraction early and Cimolai catching him on the line.
The traditional sprinters struggled on a testing day, although Andre Greipel deserves credit for making it through in the peloton. The German looked in a good place to contest for the stage win, but was boxed in as his tired legs began to fade in the final 300m and had to settle for a fifth-place finish.
Team Sky's Chris Froome made his European racing debut of the season and fared comfortably on the day. Froome is among the favourites to win the general classification, along with Alberto Contador and Alejandro Valverde.
Tuesday's stage is a 41.3 km team time trial in Banyoles.
STANDINGS AFTER STAGE ONE:
- 1. Davide Cimolai (Italy / FDJ) 4:28:11"
- 2. Nacer Bouhanni (France / Cofidis) +4"
- 3. Kristian Sbaragli (Italy / Dimension Data) +6"
- 4. Dion Smith (New Zealand / Wanty) +10"
- 5. Andre Greipel (Germany / Lotto)
- 6. Jose Joaquin Rojas (Spain / Movistar)
- 7. Daryl Impey (South Africa / Orica)
- 8. Petr Vakoc (Czech Republic / Quick-Step)
- 9. Phil Bauhaus (Germany / Sunweb)
- 10. Enrico Gasparotto (Italy / Bahrain)
With additional reporting from Reuters
Read the original article on Eurosport: Cimolai pips Bouhanni in Stage One sprint finish