Just hours after a string of deadly bombings rocked the London Underground, the subway line beneath Lexington Avenue was so packed with passengers that a painter from St. Francisville, La., Caroline Porche, 64, tied her 6-year-old granddaughter to a leash to keep track of her amid the lunchtime crowds.

After purchasing a seven-day unlimited ride MetroCard on Wednesday, Ms. Porche said she was not prepared to let her $24 investment go to waste – regardless of events on the other side of the Atlantic.

Similarly, a 31-year-old school secretary from Sheepshead Bay, Melinda Isabel, said: “What happened in London can’t stop me.”

The vast majority of the dozens of straphangers interviewed yesterday by The New York Sun said the Underground bombings had no impact on their daily routine.

“I’m not about to change my plans because of something that happened thousands of miles away,” a video producer from the West Village, Bill Kavanagh, 48, said.

A 43-year-old financial writer from Midtown, Dale Wagner, woke up to a cell-phone call from her frantic fiance, who urged her to take a cab to her Church Street office. Ms. Wagner took the subway instead.

Even as President Bush, speaking from the G-8 summit of world leaders in Scotland, urged Americans to be “extra-vigilant,” passengers and workers in the subway system reported no change in their level of caution.

A carpenter who has worked on a construction project beneath the Port Authority Bus Terminal in Midtown for the past seven months, Victor Mayer, 26, of Lakewood, N.J., said that after a three-year Army career that included a tour of duty in Bosnia, “I’m vigilant every day.”

Some New Yorkers who said the London attacks had made them more anxious about underground travel nonetheless descended in the subway system after concluding that they had no other viable means of transportation.

A 21-year-old yeshiva student from Crown Heights, Peretz Mishulovin, said he considered avoiding the subways “for a second.”

He nonetheless hopped on the no. 4 train because it was the fastest way for him to reach a Midtown travel agency, where he picked up a ticket for a flight to Kiev scheduled for yesterday evening.

“A cab? It’s not within my budget,” a 26-year-old White Plains woman, Shannon Pan, said as she boarded the subway shuttle at Grand Central en route to her office at an architecture firm in Chelsea.

Several riders said, however, that the attacks in London, the newly announced home of the 2012 Olympics, left them relieved that New York’s bid for the Games had failed.

“I was concerned that if the Olympics came here, we would have been a target,” a management consultant from Hempstead, Clyde Riggins, 39, said as he left the subway at Times Square.

“I’m happy the Olympics aren’t here,” a student at John Jay College of Criminal Justice, Emma Hamilton Seard, 21, said. Ms. Seard said she was born in London but is now a Brooklynite living in Flatbush.

A television editor from Bushwick, Lars Woodruffe, 35, said his experience living in London for two years in the late 1990s, in the aftermath of an Irish Republican Army bombing campaign, had left him accustomed to commuting amid terrorist threats against the subway system.

Even some travelers from nations that have not been rocked by terror attacks seemed to adopt a stoic attitude toward yesterday’s heightened security concerns.

Near a Chambers Street subway stop, a Dutch writer of children’s books, Martina Letterie, 46, recalled that the government of the Netherlands had distributed pamphlets at Amsterdam’s Schiphol Airport warning travelers “not to go near buildings where there are many Westerners.”

Scanning the Lower Manhattan streetscape, Ms. Letterie quipped: “That’s not a very good tip here.”