An estimated one million Catholics across the United States are expected to gather at the outdoor Sunday mass to be held at the Benjamin Franklin Parkway, which will conclude the six-day US tour of Pope Francis.

The head of the Catholic Church arrived in Philadelphia on Saturday, as part of his first visit to the United States since his election in March 2013. It is also the first papal visit to Philadelphia after 36 years --- John Paul II visited the Pennsylvania State in 1979.

The Sunday mass is also expected to be streamed in Spanish as well on 27 September, Sunday. [Watch Live Streaming of the Sunday Mass from Philadelphia.]

On Sunday morning, 27 September, the pope will meet with the bishops at St. Martin's Chapel at around 9.15am (local time). [Watch live here]. 

The 78-year-old "people's pope," at 11am will interact with some 100 inmates of Curran-Fromhold Correctional Facility.

According to reports, the Sunday mass, to be held at the Benjamin Franklin Parkway at 4 pm, is expected to see the largest of the crowds at the outdoor prayer. After the mass, the pontiff will fly back to Vatican at 8 pm.

Live streaming of the event in Philadelphia, including the Sunday mass, will also be available on Catholic TV.

Timing and schedule of Sunday itinerary of Pope Francis