The tracks are being tested on Wednesday

London Underground (LU) said all stations on the Tube network were now being served.

The Hammersmith and City Line, also shut since 7 July, reopened on Tuesday leaving the Circle Line the only one to remain closed.

The Piccadilly Line had been suspended from Hyde Park Corner to Arnos Grove and from Rayners Lane to Uxbridge.

LU described getting the line up-and-running within four weeks of the blasts as a "tremendous achievement".

I would like to pay tribute to the work of the staff ... who have done an incredible job Tim O'Toole LU Managing Director London travel news

Tim O'Toole, LU's managing director, said: "I would like to pay tribute to the work of the staff from LU, Metronet and Tube Lines who have done an incredible job in the past few weeks.

"However, at this time, we also remember those who were killed or injured on 7 July. Our thoughts are with the families of the bereaved and with those still recovering. We will never forget them."

LU also said that while the line had been suspended, Tube Lines - which along with Metronet maintains the Underground network - had carried out some improvement work at Caledonian Road, Manor House and Turnpike Lane stations.

Planned track replacement work will still take place this weekend on the Piccadilly Line from Acton Town to Hyde Park Corner, and between Earl's Court and Acton Town on the District Line.