Kaygetsu, a seven-year-old Japanese restaurant in Menlo Park that made Zagat's top 10 list and has consistently made the San Francisco Chronicle's list of best Bay Area restaurants, will shut its doors next month, according to the owners.

"We feel like we've been running non-stop and we need to stop now," said co-owner Keiko Sakuma. "We have been very fortunate to have met so many wonderful people through Kaygetsu. It is truly a bittersweet moment for us as we're saying goodbye to our customers."

The building at 325 Sharon Park Drive in Sharon Heights won't stand vacant, however. Tomonari and Keiko Mitsunobu plan to open Restaurant Mitsunobu at the same spot as soon as the liquor license transfers, probably by the second week of October, according to Ms. Sakuma, who said the seasonal menu will feature "Japanese food with a California twist." Current executive chef Shinichi Aoki will stay on.

Neither will the Sakumas stand idle. "We're retiring from the restaurant business, but we will still be working -- we can't afford to completely retire yet," Ms. Sakuma said.

As Kaygetsu prepares to close, yet another restaurant is getting ready to open. The owners of Left Bank plan to open a steakhouse at the corner of University Drive and Santa Cruz Avenue, in the space that until recently housed Marche restaurant.

The date for the grand opening "completely depends" on Menlo Park's permit process, according to spokesman Tom Walton.

Why Menlo Park? He said that after the city was selected for Left Bank in 1998, the owners came to enjoy the community, particularly events such as the Connoisseurs' Marketplace.