Michal Kwiatkowski (Team Sky) took the stage victory and race lead, riding in the colours of the Polish national time trial champion. Kwiatkowski's Team Sky teammates Gianni Moscon and Jonathan Castroviejo also finished in the top-ten while wearing the national colours of Italy and Spain respectively.
The national road championships are traditionally held on the last weekend in June, giving riders a final opportunity to show off their colours at this month's Critérium du Dauphiné and Tour de Suisse. In total, there are 12 national champions, plus the European champion in Victor Campenaerts (Lotto Soudal) at the 70th edition of the Critérium du Dauphiné, just under 10 per cent of the race starters.
Alongside the national champions' customised speedsuits, bikes, helmets and accessories, the prologue also gave an opportunity for riders to test the latest wheels and tweak their setups ahead of the team time trial on Wednesday, itself a crucial test ahead of next month's Tour de France team time trial.
Campagnolo-sponsored Movistar and Lotto Soudal had a number of riders using the new Campagnolo WTO wheel range, or Wind Tunnel Optimised, while Team Sunweb appeared to be racing with a new 4-spoke carbon front wheel from Giant.
Quick-Step Floors were another team on new, time trial-specific carbon wheels with the Roval 321 Disc carbon rears. The time trial wheels from Specialized's wheel brand were launched last month and are available in both rim or disc brake options.
Alongside a new rear wheel, Quick-Step Floors' Bob Jungels also appeared to be racing on a custom carbon saddle, likely due to help keep position where other production saddles cannot.
Several riders opted to roll to the start line in ice vests in an attempt to keep core body temperatures low in the humid conditions in Valence, while an array of fans and cooling systems were in place around the team buses while riders warmed up ahead of their start times.
Click or swipe through the gallery above to see all that was on display at the Critérium du Dauphiné time trial opener.