Although the park is officially open to travel all year, summer--June
through September--is the "regular" season. From October until May,
high-altitude roads are blocked by snow, as are most park trails in
winter. All but one of the visitor centers are closed, and naturalist
hikes and other activities are not scheduled after September 15. Camping
is difficult from September to May because of adverse weather and
limited facilities. However, the roads to both Estes Park and Grand Lake
are usually open throughout winter, and accommodations are available in
both gateway towns during the off-season.