Herzelia (Israel): What's a must?
I assume you're talking about Herzliya Pituach, the high-tech area?
On Shenkar Street, Zozobra Noodle Bar is very popular with Israelis. If you want good Italian, Joya a few doors down is good too.
On Maskit St., Sebastian is a good,bistro style restaurant. There are a number of popular, high end coffee shop/bakeries on Maskit St close to where it meets Abba Ebban, where you can sit outside and have a coffee. Also nearby is Tandoori, a good Indian restaurant run by a woman named Pushkarna who has become something of a local celebrity.
On the higher end of the scale, Roca is a great place to eat. It is on the cliff right over the sea, with outdoor seating and a kind of "chill-out" atmosphere. A favorite with celebrities. Good food and good wine list, this place is an "experience".
Herzlia has a lot of workers lunch restaurants serving authentic cuisine from Israel's various ethnic groups. Shemen, on the corner of HaSadnaot and Abba Ebban is the place for schwarma. There is a good felafel place, I don't know the name, on Abba Ebban just above Maskit on the other side of the street. On Galgalei ha Plada there is Naflis, a Yemenite restaurant that has been there for a million years. Finally, if you know someone with a car, in the adjacent suburb of Nof Yam, in the ancient little commercial center there, is a good place for Tripolitanian (Libyan) food. The restaurant has a woman's name, I can't remember, but you won't miss it. Right around the corner from it is the Sidnee Allah mosque which stands picturesquely above the sea, with a very nice, uncrowded beach below it.
Someone will probably take you to the Herzliya marina. It is a very pleasant area, and the restaurants there are nice, but nothing special.