To assault the Vinson Massif, with the support of Mountain Travel, costs $15,100, excluding airfare.

I did a photo safari a few years ago to Kenya and Tanzania with Mountain Travel.

Mountain Travel recommends this method of making the circuit in late July and August, when the lodges tend to be crowded.

Mountain Travel, the biggest American adventure travel operator, says its trek bookings are up 35 percent this year.

"That's a question we battle with all the time," said a representative of Mountain Travel, Deborah Sharkey.

Mountain Travel, having used a rather complex coding system for years, now prefers brief descriptions and has a special mountaineering section for its most difficult trips.

Mountain Travel, the tour packager I used, offers a shorter Kilimanjaro package for about $140 a day.

Mountain Travel says it spent $350,000 on its catalogue last year, a cost ultimately shouldered by about 3,000 trek customers.

Mountain Travel offers a 32-day excursion around Annapurna for $2,650, or $83 a day.

Mountain Travel got its start in trekking, Sobek in river rafting.