Period dramas are tough to film, as there are strong chances of historical inaccuracies. The same happened with the recently-released Netflix Regency drama "Bridgerton," as several twenty-first century details peeked into the supposedly Regency-era England.

Eagle-eyed viewers had been taking to Twitter to list the oversights that gave away the fact that the series was, of course, not filmed in the 18th century. One of the modern-day details was in the period drama's premiere episode, which begins with a scene showing the town square.

The scene has several people riding in horse-drawn buggies, and in one shot, a yellow traffic line can be seen atop the cobblestone street outside of Bath's Royal Crescent. The show is adapted from Julia Quinn's bestselling book series which takes place in 1813, a time when cars didn't exist. Cars weren't widely used in London until the mid-20th century, and yellow traffic lines weren't painted until the 1950s.

A Twitter user pointed out the error writing: "Oh dear, modern yellow no parking lines on the street in the tv drama 'Bridgerton'. I've worked on a few films/tv shows as historical consultant and art department, I remember our lot painting over modern white lines on a street or covering the whole street with earth."

Another user commented: "I couldn't get into Bridgerton. I got bored and the lighting bothered me, way too bright for a period drama. Also spotting inaccuracies like double yellow lines on the road."

The traffic lines were not the only modern-day details which the production team overlooked. Viewers pointed out inaccuracies like a poster for fashion retailer Primark, a manhole cover, parking signs, a doorbell, and seedless fruits.

Van Dusen has not yet reacted to the mistakes, but he previously revealed that the team relied on technology to create certain scenes on "Bridgerton." He noted that the Grosvenor Square, a real location in London's Mayfair district which was the center of town on the show, is actually completely fictional and created from a green screen.

The period drama created by Dusen and produced by Shonda Rhimes had one of the biggest debuts on Netflix last month. With 63 million households viewing the show within 28 days of its premiere, it is Netflix's fifth-largest original series launch in its history, the streaming giant tweeted.

It was renewed for a second season last week, and production is set to begin this spring. While the first season is primely centered on Daphne Bridgerton and her romance with the Duke of Hastings, the second will shift its focus to her elder brother, Lord Anthony Bridgerton.

Regé-Jean Page
Regé-Jean Page and Phoebe Dynevor in the Netflix series "Bridgerton." Bridgerton/Netflix