By SIMON ROBINSON

NORTH AMERICA

SAN FRANCISCO
Why do we remember some things and forget others? "Memory," an upcoming exhibition at the Exploratorium, asks that question and many more in an examination of personal experiences of memory and the latest developments in cognitive science. Exhibits include a human brain in a jar; a jukebox to provoke memories associated with music; and the tiny brain of a sea slug through which electrical pulses will be fired, causing visible changes to nerve cells. Visitors will have their own memories challenged by tasting various jelly beans and then listing the flavors they can recall, and may compare Italian street scenes witnessed decades ago and painted from memory by artist Franco Magnani with photographs of the streets. From May 22 through Jan. 10, 1999.

LISBON
Spanning the river Tagus, the new Vasco da Gama bridge--named for the 16th century Portugese navigator who first discovered a sea route between Europe and India--is the most visible part of a massive urban regeneration project under way in the Portugese capital. The $1 billion, 17-km toll bridge--Europe's longest--allows north- and south-bound traffic to avoid the city. Close by, a 300-ha oceanfront area dubbed Expo Urbe is being transformed with new offices, houses and shops, a huge transport hub, Europe's biggest oceanarium, and auditorium, a convention center, and a 80-ha park. The site incorporates Expo '98, Lisbon's world fair, which will open May 22.

ENGLAND
In the 15th and 16th centuries tribes of brigands known as Border Reivers rampages across northern England, raiding villages, kidnapping or killing their inhabitants. Now cyclists can retrace the steps of those bloody medieval journeys by following the new Reivers cycle route. The 225-km-long track links back roads and forest trails and runs east-west from the River Tyne to the Cumbrian coast, including a brief excursion into Scotland. It can be covered in under five days--presuming no time is spent raiding or kidnapping--and is easily combined with the popular C2C (sea to sea) route, which runs through the Lake District and the Durham Dales to Sunderland.

ASIA

WEATHER
Travelers to Southeast Asia concerned about health-threatening haze from continuing Indonesian forest fires can check the latest air pollution levels on the Web. The Singapore government's weather sire (www.gov.sg/metsin) provides daily updates on the fires and weather conditions: includes a modified satellite image showing the areas affected by haze; and marks prevailing winds on a map. The Malaysian Meteorological Service has a page (www.kjc.gov.my/people/environ/haze.htm) describing haze conditions at various points around the country. As well, tourism officials from most ASEAN member nations are issuing regional haze advisories once a week to tour operators and travel agencies in the region.