A congratulatory video about shipbuilding in the Halifax harbour posted online by the Conservatives has some viewers doing double takes.

The video was posted to Conservative Leader Stephen Harper's Facebook page on Tuesday to celebrate the start of construction on the lead vessel of the Royal Canadian Navy's new Arctic offshore patrol ships. It kicks off Irving Shipbuilding's 25-year contract to build new patrol vessels and warships in Halifax.

Harper spends all of the 36-second video touting the city's shipbuilding efforts while standing in front of a body of water and a large suspension bridge in what first appears to be Halifax. The video cuts to a grain elevator and flora (both common sights in Halifax's harbour), while Harper battles to speak over a windswept mic.

However, astute viewers realized it's not the Halifax harbour at all, but rather another, similar looking body of water and suspension bridge.

The similarity was first pointed out on Twitter.

Stephen Harper congratulates the ship building contract starting in Halifax.... but this isn't Halifax? <a href="https://t.co/U0Lgv5b72U">https://t.co/U0Lgv5b72U</a> —@Allisomething

The backdrop in the video looks like it could be Halifax's A. Murray MacKay Bridge (or the New Bridge as its known locally), with the Bedford Basin in the background.

Working off this, Twitter users tried to determine precisely where Harper was standing in the Halifax harbour when the video was filmed.

Like am I losing my mind? Is it possible maybe the McKay looks like that from a different angle? But how? It'd have to be the Basin... —@Allisomething

<a href="https://twitter.com/Allisomething">@Allisomething</a> He's standing to the north of the new bridge, on the dartmouth side, I think. It took me a lot longer than it should of. —@IneffectiveMath

<a href="https://twitter.com/Allisomething">@Allisomething</a> Maybe? Looking toward the bridge? <a href="http://t.co/DTWBFQAjUQ">pic.twitter.com/DTWBFQAjUQ</a> —@joelkelly

But they quickly noticed some inconsistencies with the Halifax shoreline – and that led to an online manhunt for the mystery bridge.

<a href="https://twitter.com/Scott_HFX">@Scott_HFX</a> <a href="https://twitter.com/Bobby_OK">@Bobby_OK</a> <a href="https://twitter.com/Tim_Bousquet">@Tim_Bousquet</a> <a href="https://twitter.com/Nicki_Doyle">@Nicki_Doyle</a> <a href="https://twitter.com/Allisomething">@Allisomething</a> It's not it. There's no blue building near it <a href="http://t.co/34ie9h9fjf">pic.twitter.com/34ie9h9fjf</a> —@halflockofoppo

<a href="https://twitter.com/Tim_Bousquet">@Tim_Bousquet</a> <a href="https://twitter.com/Nicki_Doyle">@Nicki_Doyle</a> Still trying to figure out the location of Not-Halifax. —@Scott_HFX

<a href="https://twitter.com/Tim_Bousquet">@tim_bousquet</a> <a href="https://twitter.com/Scott_HFX">@Scott_HFX</a> <a href="https://twitter.com/Nicki_Doyle">@Nicki_Doyle</a> <a href="https://twitter.com/Allisomething">@Allisomething</a> It looks an awful lot like the bridge to Ile d'Orleans in Quebec City. —@Bobby_OK

Turns out the real bridge is actually the Ogdensburg-Prescott International Bridge on the American border in Johnstown, Ont.

The bridge is about 90 kilometres outside of Ottawa and spans the St. Lawrence River between Johnstown and Ogdensburg, N.Y. A spokesperson with the Port of Johnstown identified the bridge in the video as theirs — recognizing it by the grain elevator.

There are some similarities between Halifax's MacKay bridge and the Ogdensburg-Prescott bridge in Johnstown. Both are suspension bridges and share a distinct green colour. The Port of Johnston grain elevator that is featured in the video could be mistaken for the grain towers in the Port of Halifax.

The bridge's identity was further verified by a few locals.

<a href="https://twitter.com/glen_mcgregor">@glen_mcgregor</a> Cough - as a proud Prescott resident, I can tell you it is the Prescott-Ogdensburg Bridge. —@brucejameshayes

After the revelation was made on Twitter, the complete findings were gathered in Halifax's Chronicle Herald newspaper.

This is the Ogdensburg-Prescott Bridge in Johnstown, ON. Winner winner chicken dinner? <a href="http://t.co/hxT5xOFRBC">pic.twitter.com/hxT5xOFRBC</a> —@notandrea

Conservatives say it was never meant to be Halifax.

In the video, Harper does not identify where the video is set and the description on Facebook makes no mention of location. Cory Hann, a spokesperson for the Conservative Party, said the video was never meant to be misleading. He said Harper filmed the congratulatory video for the Maritimes while out on the campaign trail.

"It was never said to be Halifax, it was never inferred to be Halifax and it was never meant to be assumed to be Halifax," Hann told CBC News in a statement.

"Given the [Ogdensburg-Prescott bridge] was featured prominently in the video, it's clear it was not Halifax."

Of course, that didn't stop people from poking fun.

"Oh I'm sure no one in Nova Scotia will realize this is neither the McKay nor the MacDonald bridge, which they see literally every day" —@anne_theriault

head + desk = slam <a href="http://t.co/Nh3DWDnSdf">http://t.co/Nh3DWDnSdf</a> —@Ginger_Polo

CPC staffer: don't you think people will know it's not Halifax? Harper: ¯\_(ツ)_/¯ <a href="https://t.co/3N62T0fM82">https://t.co/3N62T0fM82</a> —@elbrwn

It even led people to mockingly create their own interpretations of the video.

<a href="https://twitter.com/notandrea">@notandrea</a> <a href="https://twitter.com/haligonia">@haligonia</a> <a href="https://twitter.com/CBCNS">@CBCNS</a> Don't worry Mr. Harper, I've got your back <a href="https://twitter.com/hashtag/Halifax?src=hash">#Halifax</a> <a href="https://twitter.com/hashtag/CloseEnough?src=hash">#CloseEnough</a> <a href="http://t.co/csfi3GLgbR">pic.twitter.com/csfi3GLgbR</a> —@thejimpster

ICYMI: <a href="https://twitter.com/pmharper">@PMHarper</a> tries to pass off a bridge in ON as one of Halifax's iconic bridges (<a href="http://t.co/WYML9SlwTw">http://t.co/WYML9SlwTw</a>) <a href="http://t.co/CU9ZBvgZhL">pic.twitter.com/CU9ZBvgZhL</a> —@cganders

After a busy day in "Halifax", Stephen Harper gives a 1 on 1 interview with Brian Williams..I think from Moncton. <a href="http://t.co/bLIQQI3vYT">pic.twitter.com/bLIQQI3vYT</a> —@thejimpster