Around 1,000 protesters rallied on Saturday in the northeastern Romanian village of Pungesti against plans by US energy giant Chevron to drill for shale gas.
The protesters, including villagers in national dress, chanted "Chevron, go home" and "We say no to shale gas."
Chevron on Thursday suspended activities in the region after three days of protests.
But villagers have continued to occupy the site where the company plans to drill its first exploration well.
"We have won a battle but not the final victory. I want my seven great-grand-children to grow up in a safe environment," Emil Dobarteanu, 88, told AFP.
The protesters are afraid of the environmental and health impact of the highly controversial drilling method used to unlock shale gas, called hydraulic fracturing or 'fracking'.
The technique consists of pumping water and chemicals at high pressure into deep rock formations to free oil and gas, with environmentalists warning the process may contaminate ground water and even cause small earthquakes.
Film-maker Lech Kowalski, author of "Drill Baby Drill", a documentary about a Polish village fighting against Chevron's shale gas drilling plans, was among the participants.
Several hundred people also protested in the eastern city of Barlad, forming a human chain around the town hall.
They called for Prime Minister Victor Ponta's resignation, blaming him for reneging on his campaign promise to ban shale gas drilling.
Chevron has permits to explore for shale gas in three villages in this impoverished part of northeastern Romania as well as on Romania's Black Sea coast.