Engineering work is to be carried out on the tram network in Sheffield this weekend to prepare for Tram Trains to run between the city and Rotherham.
Work is to be carried out on the tramline between Meadowhall and Hyde Park on Saturday and Sunday.
Dedicated YX, Y1 and L1 bus services will replace trams between Fitzalan Square and Meadowhall over the weekend.
Revised timetables will be in operation on the yellow and purple routes, with passengers urged to check before they travel.
The work is to ensure that the plan for Tram Trains to run in South Yorkshire from 2017 remain on track.
Passengers in South Yorkshire will be the first in the country to use Tram Trains, which will provide a direct service from Sheffield city centre to Rotherham Central and Parkgate, travelling on street tramlines and the national rail network.
A South Yorkshire Passenger Transport Executive spokesman said: “Parts of the existing Supertram track are being adapted to allow Tram Train to run because Tram Train wheels are a different size to that of an existing tram.
“Overnight engineering work to alter the track has been underway since October 2015, with more complex work completed during weekends in February 2016.
“Future works to make Tram Train a reality include construction of a 400 metre new section of track called the Tinsley Chord to link the tram network to the rail line between Sheffield and Rotherham, the installation of overhead lines to carry electricity to power the vehicles, and building new Tram Train platforms at Rotherham Central and Parkgate.
“The Tram Train pilot is delivered by South Yorkshire Passenger Transport Executive, Stagecoach Supertram, Network Rail, Northern Rail, and the Department for Transport.”
Replacement bus service timetables and information can be found online at supertram.com and travelsouthyorkshire.com, by following @SCSupertram and @TSYalerts on Twitter and by calling Traveline on 01709 515151.
There will also be posters at tram stops.