July 4 - Fort Laramie:
At Fort Laramie James Reed ran into an old friend from Illinois by the name of James Clyman, who had just traveled the new route eastwardly with Lansford Hastings. Clyman advised Reed not to take the Hastings Route, stating that the road was barely passable on foot and would be impossible with wagons. Reed ignored his warning.

They were joined by other parties along the way until its size numbered 87.

Source: PBS WBGH

In Fort Laramie, the pioneers were met by a man carrying a letter from Lansford W. Hastings at the Continental Divide on July 11th. The letter stated that Hastings would meet the emigrants at Fort Bridger and lead them on his cutoff

July 28 - Bridger's Fort - Hastings Cutoff :
On July 19th the train split, with the majority of the large caravan taking the safer route. The group preferring the Hastings route elected George Donner as their captain and soon began the southerly route, reaching Fort Bridger on July 28th. However, when they arrived at Fort Bridger, there was only a note indicating that Hastings had left with another group and that later travelers should follow and catch up. Jim Bridger and his partner Louis Vasquez assured the Donner Party that the Hastings Cutoff was a good route.

On August 6, the party reached the Weber River after having passed through Echo Canyon. Here they came to a halt when they found a note from Hastings advising them not to follow him down Weber Canyon as it was virtually impassible, but rather to take another trail through the Salt Basin.

On August 11th, the wagon train began the arduous journey through the Wasatch Mountains, clearing trees and other obstructions along the new path of their journey. In the beginning, the wagon train was lucky to make even two miles per day, taking them six days just to travel eight miles.

The Donner Party now numbered 87 people in 23 wagons.

Aug. 30 - Great Salt Lake:
Hastings told them it would take 2 days to cross the Great Salt Lake but the sand was wet and it took them 5 days. On their eighty mile journey through the Salt Lake Desert, they had lost a total of thirty-two oxen; Reed was forced to abandon two of his wagons, and the Donners, as well as man named Louis Keseberg, lost one wagon each.

Realizing that the difficult journey through the mountains and the desert had depleted their supplies, two of the young men traveling with the party, William McCutcheon and Charles Stanton, were sent ahead to Sutter’s Fort, California to bring back supplies.

The disillusioned party’s resentment of Hastings, and ultimately, Reed, was increased tremendously.

Sept 20 Join back up with the Calif. Trail (Nevada):
The Donner Party soon reached the junction with the California Trail, about seven miles west of present-day Elko, Nevada and spent the next two weeks traveling along the Humboldt River. As the disillusionment of the party increased, tempers began to flare in the group.

on October 12th, their oxen were attacked by Piute Indians, killing 21 one of them with poison tipped arrows, further depleting their draft animals.

Oct. 31 - Donner Lake:
They reached Donner Lake at the end of October when it started to snow. After attempting to make the pass through the heavy snow, finally retreated to the eastern end of the lake, where level ground and timber was abundant.

On Thanksgiving, it began to snow again, and the pioneers at Donner Lake killed the last of their oxen for food on November 29th. The very next day, five more feet of snow fell, and they knew that any plans for a departure were dashed.
They had come 2,500 miles in seven months to lose their race with the weather by one day, only 150 miles from their destination of Sutter's Fort.

Realizing that they were stranded, the main body erected cabins along Truckee Lake and a smaller body that consisted of the Donner family and their hired men made a camp of tents several miles back at Alder Creek.

Dec 15 - First to die of starvation:
On December 15, Balis Williams died of malnutrition and the group realized that something had to be done before they all died. The next day five men, nine women and one child departed on snow shoes, but only seven of them survived to reach Sutter's fort. Several other attempts were made by small groups at crossing the mountains.

Feb. 19 - First Rescue Party:
On February 19th, the first rescue party reached the lake finding what appeared to be a deserted camp until the ghostly figure of a woman appeared. Twelve of the emigrants were dead and of the forty-eight remaining, many had gone crazy or were barely clinging to life. However, the nightmare was by no means over. Not everyone could be taken out at one time and since no pack animals could be brought in, few food supplies were brought in.
Other relief parties arrived in March and April to finding grisly evidence of cannibalism.

April 29 - Last member reaches Sutters Fort:
The last member of the Donner Party arrived at Sutter’s Fort on April 29th.

In the Donner Party tragedy, two-thirds of the men in the party perished, while two-thirds of the women and children lived. Forty-one individuals died, and forty-six survived. In the end, five had died before reaching the mountains, thirty-five perished either at the mountain camps or trying to cross the mountains, and one died just after reaching the valley. Many of those who survived lost toes to frostbite.

The story of the Donner tragedy quickly spread across the country. Newspapers printed letters and diaries, and accused the travelers of bad conduct, cannibalism, and even murder. The surviving members had differing viewpoints, biases and recollections so what actually happened was never extremely clear. Some blamed the power hungry Lansford W. Hastings for the tragedy, while others blamed James Reed for not heeding Clyman’s warning about the deadly route.

Emigration to California fell off sharply until January 1848 when gold was discovered.

"Remember, if you come this way, don't take no shortcuts and hurry along as fast as you can." (Virginia Reed, Age 12, Donner Party Survivor, 1847)

Sources: The History of The Donner Party at The Green Lantern Press
Ordeal by Hunger: The Story of the Donner Party, 1963 by George R. Stewart
The Donner Party, PBS/The American Experience (WGBH Educational Foundation, 1997)

Links:
The Fateful Journey of the Donner Party at Virginia Western