Until now they've mostly been limited to large overseas cities such as Hong Kong and Barcelona. But Sydney is about to join the ranks of cities sporting a lift-only entrance to a train station.

Among a raft of modifications to the second stage of the city's $20 billion-plus metro rail line, Transport for NSW has proposed building four lifts each capable of carrying up to 27 people at the northern entrance to Victoria Cross Station at North Sydney.

Patronage for the new underground station is forecast to reach 42,100 people a day by 2026, and 45,500 by 2036, which the government's transport agency says supports the case for a second entrance on McLaren Street for Victoria Cross.

Based on the forecast patronage, a Transport for NSW report on the proposed changes predicts a maximum queue for the lifts of 20 people and wait time of 21 seconds when all four are in operation.