The luxury five-star Serena Hotel in Pakistan's capital has become the unlikely venue for peace talks aimed at ending the Iran war, cementing its status as one of Islamabad's most heavily fortified buildings.

The city is under unprecedented security ahead of the talks, with shops and offices shut for two days ahead of the arrival of U.S. Vice President JD Vance, who is leading the American delegation, and senior Iranian officials.

Thousands of security personnel, including paramilitary and army troops, have set up checkpoints and blockades across the capital, cordoning off the Red Zone where government offices and embassies are located.

The Serena may appear to be an odd choice to host the high-stakes talks, particularly since Islamabad's worst militant attack took place in 2008 at the nearby Marriott hotel, but its picturesque grounds and Moorish architecture belie what security officials describe as a well-oiled security setup.

They and former police chiefs pointed to its strategic location close to the diplomatic zone and years of maintaining the safety of high-profile guests.

"Its security staff is well trained as most of them are retired security officials," said former Islamabad police chief Tahir Alam Khan.

"The entry and exit points are at an adequate distance from the main compound which enhances its security. And the most important factor is its smooth access from the important places such as the Prime Minister's House, Parliament House."

A government security source said the hotel's 15-acre premises - which include more than 400 rooms, multiple banquet halls, conference rooms and an office complex - can house hundreds of guests, ideal for the U.S. and Iran delegations which comprise over 150 people.

"It has multi-layered, strict security checks... lastly it has strong coordination with the state's security agencies," said Kaleem Imam, another former police chief.