The Palace of Westminstergates through which a terrorist gained entry to the Parliamentary estate and killed a police officer have been replaced.
The existing Carriage Gates were removed on Tuesday and a pair of bulkier, less decorative gates constructed out of square metal tubing and covered in wire mesh were installed instead.
It was not immediately clear if the change was made for security reasons or if the existing gates have simply been taken away for maintenance.
The Carriage Gates entrance to Parliament was breached on March 22 when terrorist Adrian Ajao rushed into the parliamentary estate after abandoning his car.
Mr Ajao stabbed unarmed officer Pc Keith Palmer to death and was able to get 20 yards into the estate before being shot.
The replacement of the gates comes one day after the funeral of Pc Palmer when the hearse carrying his body passed through them on the way to a service at Southwark Cathedral.
More than 5,000 officers lined the streets of London alongside thousands of members of the public in what is believed to have been the country’s biggest ever police funeral.
The security of Carriage Gates has received intense scrutiny in the wake of the terror attack which left five people dead as well as the attacker.
This newspaper uncovered a number of previous incidents at the entrance - which is often opened to let in ministerial cars for votes and debates - in recent years.
For example, the gates were breached last year by an intruder who walked straight past guards with officers fooled by a fake identification which allowed the 29-year-old to enter despite not being security cleared.
The intruder was able to wander the parliamentary estate for half a day before being caught in a major breach of security.
Commons Speaker John Bercow announced at the end of March that two reviews into security in Parliament will be held following the terror attack.
An independent review will take place into how the perimeter fence of the Parliamentary estate is secured with a second externally-led review into how Parliament responds to major incidents.