The mountaintop settlement of Koyasan is one of the best places in Japan to stay overnight in a temple and experience Buddhist morning ceremonies. More than 100 temples surround the center of esoteric Shingon Buddhism, and some 50 temples open their doors to guests. Dinner is usually served in the temple at 5:30, followed by a traditional Japanese bath.

Since no car is needed in Koyasan, the best—and quickest—way to reach it is by train from the Nankai private railway terminus, in central Osaka's Namba Station. Choose either an express or a "limited express" (the faster option) to Gokurakubashi; from there you take a cable car up the mountain ($11 one way).

It's generally easy to find accommodations upon arrival. From the cable car take the No. 2 (Okunoin) bus to the Senjuinbashi stop (280 yen, or $2.50), where you'll find a Tourist Information Office, with an English-speaking staff, across from the post office. The temples differ dramatically in size, feeling, and services: Some can accommodate as many as 300 people (tour buses are double-parked outside them), while others are tiny and seemingly uncared for. Some have elaborate morning services, including a goma fire ceremony; others are more perfunctory. Some serve you dinner in your room; others do so in a large public space. Rates are cash only and reflect the amount of food served (8 bowls or 12) and whether, say, you require a private toilet (9,000 to 19,000 yen, or about $75 to $155). You can also book in advance through a Japanese travel agency such as JTB (212-698-4900, in New York; jtbusa.com); through the Koyasan Lodging Office, which is also cash only (56-2616; shukubo.jp/eng); or by contacting a temple directly.

While in Koyasan, you'll want to visit the most important site, the graves around the Okunoin. A single pass gets you into Kongobuji, the buildings of the Garan, and the excellent Reihokan Museum and is good for two days ($13). Try to include Kobo Daishi's mausoleum, which can be beautifully atmospheric.

There are buses that will take you everywhere on the mountain, but after the five-minute ride into town from the cable car station, you can do almost everything on foot; the Tourist Information Office at the station can give you details on several traditional pilgrim routes through and around Koyasan, including the Women's Pilgrim Route, once open only to females, that skirts the edges of the holy sites.

If you want a local to show you around, contact Kaori Kodama (73-5605; kodama@silver.ocm.me.jp) or Noriko Matsuyama (54-2172; logos@cypress.ne.jp). Both women—together with a network of volunteer guides—speak good English and can organize morning or afternoon tours (half day, $9 per person; full day, $26–$43).

The telephone code for Koyasan is 81-736. Prices quoted are for April 2007.

Lodging
All the temples have monks who speak enough English. Sekishoin has gorgeous four-room suites, but the service is somewhat brusque, as is the 20-minute ceremony in the morning (56-2734; sekishoin.net, in Japanese; doubles, $156–$312). Muryokoin is rather spartan and grungy, but the morning service is dramatic and detailed (56-2104; muryoko@cypress.ne.jp; doubles, $148–$198). Ekoin strikes a nice balance, with modest rooms, an interesting service, reading spaces around the table, and an Internet alcove (56-2514; ekoin@mbox.co.jp; doubles, $166–$198).

Locals suggest Soji-in for its well-appointed rooms (56-2111; doubles, $278), Ichijoin for Internet in every room and Shingon meditation (56-2214; doubles, $248–$280), and Jofukuin for private Japanese-style baths (56-2109; doubles, $116). I once invited the tourist office to choose a place for me and was very happy with the result.

Dining
Temples serve breakfast and dinner, so for lunch or snacks head to the spotless Bon On Sha, which has good and healthy pies and cakes, chai, and espresso and offers the best English-language conversation in town. Run by a young Japanese traveler and his French wife, it's about halfway between the central tourist office and the Ichi-no-hashi, "Bridge at the Start" (open 9 a.m.–6 p.m.; lunch, about $10).

Reading
To explore the history of Shingon Buddhism, pick up a copy of the Reihokan Museum's useful exhibition catalog, "Sacred Treasures of Mount Koya" ($35). The Koyasan Tourist Association's detailed English-language Web site, shukubo.jp/eng, has an overview of the area, a list of accommodations and amenities, and downloadable walking guides.